Uti or pregnant? HELP

I had unprotected sex a week ago and he finished in me but before that I hadn’t had sex for 3 months ago! I’m on the combined pill and I’ve never missed one but I do sometimes take it a few hours out.

3 days ago I started to notice uti symptoms (burning, frequency, one time there was blood but only once) but the burning stopped the next day and haven’t had it since.

The frequency got less but it’s still more than normal and last night I started getting a horrible ache/cramp in my left side and pelvis.

Could this be a kidney infection? I’m going to take a sample to the doctors but I’m just trying to calm myself down as I’m super panicking that I could be pregnant. It’s just a uti/kidney infection right!?

Don’t know if it’s relevant but I’ve drink about 3 times more alcohol just in this week than I normally would. Could that effect me like this?