Boyfriend stubborn about going to the doctor

Ha

Does anyone else have this issue? My boyfriend told me the other day his side has been hurting for 3 weeks and he just barely told me. I told him he needed to go to the doctor and he was like "No, I'll be okay." He's just really stubborn about it and I keep telling him, what if it's something serious? You need to go to see what's going on. I love him very much and can't imagine anything happening to him. Any advice? 😕 He's 22 and his job requires a lot of hard labor..so I thought he may have pulled something..but 3 weeks is a long time for it to still be hurting.