Sore and tender for several days would make me think its not just simple irritation, and you should be checking things out with your doctor at this point.
I agree with Daisy, the fact that your penis is sore and tender is probably a result of the rough sex, not STD. In any case, while the likelihood that you acquired an STD from this incident is low (especially since she told you she does not have an STD), it would be a good idea to get tested because of the unprotected intercourse (even if it was only 2 minutes). Yearly STD testing is recommended for people who are sexually active, but not in monogomous relationships.
Your penis being tender is most likely due to the rough sex,however any form of unprotected sex carries with it the risk of STD's the fact that it was only 2mins is irrellevant so to err on the side of caution I think it would be wise to be tested to rule out any STD transmission and also for your own peace of mind particularly when this was a stranger whos status you don't know for sure.