I want to throw my boyfriend's computer at a wall

We were supposed to go meet my grandma today, she lives an hour and a half away. He claims his jaw is killing him. So I feel hes in pain, and I take care of him then I start to get pissed off now I can't go to to my grandma's and if he had just gone to the dentist last week it wouldn't be bothering him. How convenient that his jaw is bothering him the morning he has to go meet some of my family his jaw hurts when it hasn't for a week now.

How convenient that an hour after him finding out we're not going his jaw stops hurting.

So we go get Chinese I'm feeling so awful the whole time about bailing on my grandma, I make this known to him and he acts like it's nothing.

So after an hour I decided I was going to go alone, he can take care of himself he took some pain relievers and was asleep so I check the traffic on Google maps. It would've taken me almost 3 to get there, to stay for 3 since I have work tomorrow morning. I called her to say I would still do it but she told me to stay and take care of him she rather me come next week so I can spend a whole day with her.

I normally don't get mad when he plays video games but he's been on his computer playing a game for over 6 hours now and I have to leave in an hour.

He's got plenty of time to play after I leave but he chooses while I'm here to play when we barely see each other because of our work schedules why wouldn't I want to spend time with him when I finally get to see him instead of watching him play a game for this long.

Usually when I ask him to get off he gets off right away but he won't today.

Ughhhhhhh

UPDATE: I talked to my best friend at work who's much older and more knowledgeable about these things and she said maybe it was psychological, that his jaw hurt because he was nervous about meeting my grandma so I'm going to talk to him tonight about it and bring it up