What to do

My boyfriend really wants me to go out and do something with him this weekend, but I really don't want to. I'm not interested in what he wants to do and I don't understand why he wants to do everything together. He and I have been talking about how we need to go out and do more things together and I understand that we don't do that much so I am totally up for going out more, but I don't think we need to do everything together. I wouldn't ask him to go get a pedicure with me, so why can't he understand that I really just don't want to go. It doesn't mean I don't want to do anything with him, just not that thing. He's making me feel bad for saying no and even though I've told him multiple times that I'm not interested in going, he still says I can make up my mind come Sunday. I just don't get it

The thing he wants me to do is go to a race. It will be loud and hot and I will only be there for his company, not for my enjoyment at all