Is it normal that my boyfriend rubs his private and butt at night?

Ok...I have a boyfriend that I'm completely in love with. I was wondering if it was normal for him to rub is butt and then rub his private area all night long. I hurt my back like a couple weeks ago and he was sweet enough not to pressure me into sex. I would however give him amazing BJ's and then we would go to sleep. About a month ago I confronted him about watching porn and not having sex with me. I'm more than willing and he actually told me he is tired all the time (he works 12 hours shifts) and that was why he didn't want me to bother him with sex until his days off. That was hard for me already do to the fact that I love sex. I'm horny all of the time. So a few nights ago I woke up because the bed was kind of shaking and I saw that he was rubbing his private. He looked over to me to see if I was awake and I pretended to be asleep. The thing is is that he did it like for most of the night...he would rub his private or his butt and then stop and kind of try to sleep but then start back up. I noticed this pattern again the next night and when he got up to go to the bathroom I asked him if he need me to help him out...like relax him so he could sleep. He told me he was fine and when he thought I was asleep again he started all over. So I guess my question is...Is it normal? Is it me? I'm offering to help him out and he still refuses? I'm better now and we have had sex but he still is doing it? Do I confront him? I guess I wouldN'T worry but he seems to be so tired the next day and he works long long hours and truck drives. What do I do? I don't think it's me when I would f* him, make love with him, whenever, where ever and however. (A little background...Hes 32 I'm 26. He's only been with 2 girls, while I've been with way more. He has watched porn for about 14 years and has stopped cold turkey.)ADVICE.....