Am I pregnant

So I had unprotected sex but it lasted about 2 minutes not even that and he didn't do anything because I don't want to pregnant this early, atm ive just come off my pill and coming on to my period today I had bleeding but it was very light like a red pink colour and now I have brown discharge, I'm very sore and itchy and I don't know if it's an infection as I had a water infection the other day or I'm pregnant , also I keep needing the toilet constantly then it burns and then I feel like I need to go again