I was told by a girl I just met that I seem like a 'genuinely nice' guy and she seemed interested in me, however I then felt scared and anxious about how I was going to continue this impression to the point where I was nervous around her and avoided her just in case I wasn't the same person she originally met. :(

When I first meet someone I am the truest form of myself, there's no pressure to be cool or interesting I'm not worried about what's happening because I don't think I'm ever going to see this person again, I am me and I love being that person.

How do I continue being this version of myself past the first encounter?