I think it's just the fact that you saw a syringe and you got scared the same way a person might see blood on a door handle or floor,the thing to remember is that HIV is such a fragile virus outside the body that it just can't survive the elements and therefore in becomes inactive and loses it's ability to infect you.
okay, it didn't prick me that I can remember. I checked my skin that wasn't covered by my shoes for marks and saw light ones,, but that might not be from a needle? i am just being crazy. i was a couple feet away from the needle.
You can stop worrying right now because you had no risk at all of HIV transmission because to start with the HIV virus does not survive on the tip of a syringe because the blood is exposed to the elements,secondly it would never get through your shoes and finally you can relax and put all this behind you.All the best.