running during pregnancy

I have been working out before my pregnancy. I quit running long distance every year from October-march because of the cold. But I have been doing sprints, weightlifting and metabolic. My doctor said it would be okay to slow back into long distance running. I went for my first run last night (2.5 miles) I was able to keep a conversation with my friend and felt great! This morning I'm having pelvic pain but nothing else hurts. I called my doctor to ask if this is normal. Any ideas or anyone else experience this?