I respect the fact that you're thinking about your boyfriend's comfort during sex. Tending to a person's needs and respecting their boundaries is just as important to sex as pleasure.
I'm reading the words you've written -
i think i accidentally kept going
i stopped when he pulled away
i did talk to him and he said that it was fine that it really doesn’t bother him
- and it sounds like you didn't mean to cause harm, and likely did not. So, where is the guilt coming from? Did you tell him about your guilt?
I feel that another line of questioning is in order: did you continue this behavior after he told you not to? Did you do so with the intention of violating his boundaries? As in, did you have the thought of continuing despite his preferences?
The reason I'm asking these questions is because I'm trying to give examples where the behavior would absolutely be unacceptable to measure your own actions with. It sounds like you weren't purposely trying to cause him discomfort, nor were you necessarily putting your pleasure above his at his expense. However, I will pose these questions anyway because, though your description of things makes it sound like it's unlikely that you caused harm, we can still think about how to draw these lines that lead us to reduce harm whenever possible. What steps are you taking as an individual to make sure that your boyfriend is okay?
Ultimately, the best way to know whether you made your partner uncomfortable is to ask them and to allow them the space to comfortably express any possible negative feelings.
It's good that you care. Just remember to show it!