Weird smell and urge to always go pee

So a few days ago I had sex without a condom and on no sort of birth control.. risky I know. I’m starting to get that urge where I need to keep going for a wee, then when I sit on the toilet, only a drop comes out. There is also a weird smell too. The last time I had sex previous to this was back in April last year. Would this be because my body isn’t used to it? Is this a UTI and how do I treat asap please?