scared and concerned

hi. i'm a male 30 years old. my concern is, about 7 days ago, i was out of town and at a bar late. i had a hotel room and met some people there and they came back to the room where we had some drinks. we were all drunk. the one couple left after a while and this one older woman remained. (about 40) she made it obvious she was interested in having sex but i had no protection so turned down the offer, i also felt as though i was gonna fall asleep. this was at about 6am. she was clearly upset and said i probably wanted her to leave. i said no its not like that, she could stay and i fell asleep shortly after on one of the 2 beds she was on the other. when i woke up the next morning around 10am, she was gone and i checked out and left. the next day i started to panic about what she could of done to me while i was sleeping. my main concern is that she took a needle and injected me with hiv infected blood. although it was a full day later i checked myself and couldn't find any marks on my body, but still i'm in a panic! i started reading about hiv early symptoms on the net and in the last day (six days after the event) i've got dry mouth! is this just anxiety do you think or something more serious. the more i analyze it the more i freak out. i'm so disappointed in myself that i would put myself in a possition like that with a person i know nothing about. the most worrisome thing is that i didn't want to fall asleep and thae last thing i remember about her is that she was put off/iretated with me.
what do you think, am i completly over reacting?
thanks