I was very interested by your 'poss. bullseye' - several months ago I had a 'painful spot' appear on my buttock - at the same place or very near to the 'tick-bite' - this was over a year after bite. At first I thought it was just 'a spot' [zit!?] - but it grew to about 3 inches in diam. was red with a small black centre - it stayed for several weeks and I can still see a 'mark' there. I looked through loads of pics. of bullseyes etc; and it did look like some of the 'small' bullseye pictures.!!
If it's a lyme bullseye it will probably expand and stay for awhile.
I don't think you're paranoid, just cautious.
Keep trying to get a photo of it, and write down what date and time you take the photos, so you have a progressive record of changes. And try to get a ruler into the photo so measurements are clear.
I know, it's hard to do. I was recently trying to document a bite on the back of my thigh, and if THAT wasn't funny...between a mirror, and the cell phone camera, and the ruler, and making sure the light was right ... ha!
About whether the bugs make *additional* rashes like that, I don't know. Sorry!
(I had an MD tell me my latest bite wasn't from a tick, so I deleted all the photos off my cell phone, and THEN I saw a photo in a book that was pretty darn close to what mine had looked like ... but now I have no proof!)