The other morning when I woke up to the bed shaking, I realized my husband was pleasuring himself without me. I didn't know what to do and felt like I was intruding so I just pretended I was still sleeping until it was over. When I shifted my position to lay on my side, my husband jumped right off of the bed. He definitely wanted to keep it a secret. This is the second or third time this has happened. Meanwhile its been at least 6 weeks since we have had intercourse. Is this normal or should I be worried?