DAE have to fight off the urge to block a potential partner?

I just started officially being in a relationship with this girl who lives about 2 hours away, so we haven’t met in person quite yet, but I have this issue right now which I have a lot in this type of situation where I really want to block her and just pretend none of this ever happened. I want to get to try to make this work, and everything is going great so far, but something in the back of my head just tells me to block her and give up, and I’ve done this before. Does anyone else do this? If so, please tell me how I can get over this feeling , because it sucks not knowing how I feel, and I feel like I’m lying to her and myself about how I feel.