dating advice

i’m 20 and the dating world is quite a weird world but i need advice on not self sabotage. i find myself liking someone but a part of me wants to ruin it? i feel like i become overly sensitive by little things and im not quite sure what it is, i end up saying something out of urge and instantly regretting it because i know its a bad look. almost as if im self aware, its nothing terrible but enough to know where i look like a bit of a dickhead. i want this spiral to stop or find a reason to why my brain feels the need to do this. i’ve had relationships in the past and have been fine but it’s always talking stages. is it because i don’t actually like them?