Hard to fall in love? Never been in a long time relationship?

Have anyone been in a situation when you're dating someone (because you lowkey like them ofc) and mid-way you have a hard time "breathing" (often lessen your time talking to them because you're uncomfortable for some reason) and they didn't do anything wrong to you.

I have a hard time with this problem all my life and I don't know if I'm the only one.