Hm and this is before she even makes you cum?? Have you tried going with the ol 69 occasionally if the ladies up for it. Maybe some type of natural herb just 2 give your libido that extra "Umph" Ummm..... maybe some type of sensitizing lube or something you haven't tried yet just so it will freshin it up a bit, give it just a little bit of a different sensation when you are done taking care of her. Honestly though I'm 21 soooooo well you know, I'm just pulling ideas outta my butt no real 1st hand experience with that speed bump yet.
Just don't get too worked up over it or it will make matters worse I'm sure you will figure it alllll out.