Do I have vaginismus?

I was diagnosed with vaginismus a while back, but I’m not sure what the cause of my pain is. I have no issues inserting a tampon. If I press against the wall right in the opening of my vaginal hole, it burns a little but not too bad. It usually hurts at the beginning of sex, but sometimes I can have sex pain-free. Most of the time, it hurts the day after or starts hurting if having sex for too long. Could it be a weak pelvic floor? It’s so annoying because I really want to have sex without having to worry about pain.
I really appreciate any help you can provide.