Oh my aching back!!!

Wow this pregnancy has been hard! From the morning sickness, to getting colds, to getting the stomach flu, now my back! AHHHH!!!!!!! Before I got pregnant with Aiden I was a very avid runner. I ran 4-5 miles about 4-5 times a week with the jogging stroller. (It is the best all over body work out and it help me lose all the baby weight with Syd)In November of 08 I had strained a muscle in my lower back and I had to lay off of it for a few weeks. Well during that time I found out I was pregnant and my back had kinda healed but was still tender. So I decided to refrain from running just to prevent it from getting worse. When my belly started petruding in March..oh my gosh!!! It felt like there was a knife stuck back there! As time has gone on it is just getting worse. My dr thinks it is sciatica. I'm bordering bedrest right now and I'm afraid when I go in next Wednesday for my checkup that my dr. will "officially" put me on bedrest!! YIKES! With 2 other kiddos to tend to?? Yea right doc..
I am a very active person so this is making me go bananas! I despise sitting still! Maybe this will magically dissapear? I so hope so, I can't imagine what my 9th month will be like in July if I feel like this at 6mo!