Eaten Alive

So I come to you with my most crazy-making problem this spring: ITCHY SKIN.  Mainly spider bites, I believe, though my skin seems to be reacting to any possible irritant so it's hard to tell. 

1. Awhile ago (around Mother's Day) it started with two bites on my lower back about five inches apart, and one on my right thigh -- these got pretty big and welty and were very itchy, and the one on my leg had a purplish hue after a day or so, then they went away. 
2. Then another couple of weeks later, my left forearm itched and I absentmindely scratched it, only to see three hives/welts come up with large red, swollen circles around them, so that my whole forearm was rather enflamed and very itchy/irritated.  I went to my doctor (my general practitioner) who was stumped, but determined it was definitely not bed bug bites (which was my greatest nightmare) but some sort of skin allergy.  She called it Contact Dermatitis and prescribed steroid cream for the itching.  She said if it didn't improve in a day or two that I should see a dermatologist.  Well, it improved slowly and I figured the cream fixed it, and I also took a break from wearing synthetic materials in case they bothered my skin.  This particular problem happened the morning after I shaved my forearm (which I've since stopped doing), applied self-tanner, and then wore a new, tight-sleeved cardigan with acrylic materials in it.
3. Then last Thursday, June 2, a red irritated circle with a tail extending downward appeared on the underside of my right upper arm.  It itched like hell, and I used the steroid cream.  Finally after a day or two I could see the bite in the center, and I determined it was possibly a spider bite or a really bad reaction to an otherwise unknown bug bite.  It went away in about three days, and the cream helped a bit, as did taking Benedryl at night.  (Once that wears off, the itch wakes me up.)
4. And again, this past Monday evening, I realize I have an itch on the same arm, but on the underside of my elbow.  I saw a small bump/bite with a red tail and put the steroid cream on it right away, which seemed to reduce the size of the welt and help the itching.  I thought I'd conquered it!  And then yesterday morning, it was big and red and angry and so, so itchy and irritating.  I still think spider bite, and I did some more internet research -- I saw a photo of a similar-looking bite and the guy said his red trail grew longer and was the poision going towards his blood stream.  His moved quickly so he went to the ER, and they stopped the spreading, but my "red trail" isn't growing or anything.  I used the steroid cream again all day yesterday and took Benedryl last night, then today consulted with Britch, my pre-med/biology expert, aka personal physician.  She advised me to use Benedryl cream (or spray) as it sounds like part of the red welting is my allergic reaction to the bite/venom, so something to help reduce itching plus stop allergens would be better.  I bought some around 11 this morning and it seems to feel a bit better, plus the main center of the bite isn't as red and angry-looking.  That said, there is a red halo forming around the outside (don't worry, this is not Lyme disease!) that I think is the irritation/infection dissipating, but my co-workers are all encouraging me to go to a dermatologist. 

Here is how it looked this morning:

And here's how it looks now:

Slightly better?

5.     And finally, the reasons to NOT seek medical attention are the following:

1. According to my research, the danger would come when red streaks are spreading outward, which mine are not -- they've stayed at the same place since they first appeared.
2. I don't currently have a dermatologist, so I would be attempting to be a new patient for one, and it's highly unlikely they could see me right away.
3. My co-pay is $50 for a specialty appointment.
4. Also according to my research, the doctor would only treat the symptoms, probably prescribing antiobiotics if an infection were possible, but what looks like an infection is more likely just the allergic reaction.  And if I take antibiotics, it will mess with my birth control. 
5. I think things are improving, not getting worse, judging by the amount of discomfort/irritation, and if I have a minor infection, I think I can recover just fine.  I may have a slight fever, but it's hard to tell in this heat wave.  My forehead is only a little clammy.

If anyone has any knowledge or wisdom to share, please do so.  I'm also investigating ways to repel spiders while I sleep.  I read that they don't like natural oils, so I diluted some lavender and citronella oils in water and sprayed all around my bed last night, and I intend to keep doing so -- plus give the room another good vacuuming.  Otherwise, I'm at a loss, and these are highly disruptive bites.  Help, please.

Oh, and I am ruling out bed bugs.  Don't make me crazier, people.  The bites are spaced out in time and on my body, and they're huge reactions, and the bed is fully zipped up and we've investigated it for any evidence, finding none, plus my parents slept in my bed a few weeks ago, as has Hike, and nobody else has any issues.