Before becoming pregnant I ran around 15 miles a week and did some weight training but all that stopped my first trimester. I was so sick I lost 5lbs my second month pregnant and all I did was work and sleep. Now that I'm in my second trimester and am not quite as sick I'd like to get back to working out but don't know how to get started without running, which I know I won't be able to do since walking up the stairs at work winds me. I've started having hip/pelvic pain and am hoping that exercising will help with that. Can I go back to weight training with lighter weights after taking 13 weeks off?