Headache/migraine before ejaculation!?!?

My husband just started having this. It Is so bad that he has to immediately stop. He is going to see the dr on Thursday because his mom said see started getting headaches because of high blood pressure (lol he didn't tell his mom the real reason he was getting them he just said it was when he was working) I think it is because he has been doing a little more physical labor at work and pulled a muscle in his neck/back but he won't go to the chiropractor. Has any one had this problem at all and caused it