I felt this way with my first few tattoos. I planned them out carefully, researched the best artists, and ended up with really nice tattoos. But there were always moments in the first few months after a new one where I would have anxiety or panicky feelings of "was this really a good idea?" This was especially true when a new tattoo was healing, because healing tattoos are ugly. Or at least, mine are.
Now I have a lot of tattoos and new ones don't make me anxious. Someone mentioned up thread the idea that at first you're a tattoo spectator and then you become a tattooed person/member of the tattooed community. It's an identity shift. I think that's really true. I'm all in now, and I have no regrets about any of my tattoos.