sub or dominant

This is pretty simple.

- If you like it, say "yes" clearly.
- If you don't like it, say "no" clearly.

If you aren't sure, then talk it out in a non-sexual situation. Talk when you are in a restaurant (you don't talk about this in bed).

Often people who do BDSM have a contract. When I start this type relationship, I have my partner make three lists. The first is the list of things she definitely wants/likes. The second is the list of things that she definitely doesn't want (and are off the table). The third are the "edge" cases, things that she might like and might want to try, but in a safe way. I will proceed with caution and will stop as soon as she stops having fun. At times I will make the same kind of lists.

Consent should be clear. You should have a clear agreement about what you want and what you don't want. It sounds like you haven't done this in your relationship.

Do you have a safe word?

Can you make up your mind which of you two posts is the story you want to try out here? Neither is credible, however.