I went to the doctor yesterday because I have been experiencing pain in my chest and left arm (no, it's not a heart attack!). It ends up that the pain in my chest is a muscle strain (probably from carrying Big around, trying to keep him from getting away, etc.), and the pain in my arm is an ulnar nerve issue from doing repetitive movements with my arm. The doctor told me to take it easy for a few weeks and cease doing the activities that are causing my problems (and take lots of ibuprofen).
(So, sorry Big! Looks like you're on your own. I know you can't walk yet, but I can't pick you up anymore. You'll get used to the gravel digging into your knees!) Seriously, though, my whole workout routine is out the window! ALL of the workouts I have been doing have repetitive arm movements! Is there any upper body workout that doesn't contain them?! What about blogging?! Is that too much of a repetitive arm movement, too?
I had this same nerve problem a few years ago (I did Nordic Track and jumped rope back then, too--because they work!), but I don't know that it has ever gotten completely better. If it doesn't resolve then the doctor said surgery might be in order. Nice!