ok I am only 11 weeks pregnant right now and i am having constant low back pain. I heard you can have back pain come your third trimester, but i am not even in my second one yet!
I had previously hurt my back in an accident and for a while it was relly just nothing i thought to worry about but about two weeks ago i started having sharper pains and sometimes when i sneezed it would rattle me so bad that i couldn't move for a moment, it hurt so bad.
Is it just the previous injury or is it because of the pregnancy or both? Please help!

at 11 weeks i doubt it is pain due to pregnancy, the baby is still smaller then your womb & still not much fluid, so not heavy enough to give you CONSTANT back pain.
i would def see a doc for support, maybe he could recommend some excercises to strethen your back, b/c in the third termister you will be carrying an extra 13 pounds on your front alone!
i have a tiny frame & b/c my lower back wasnt strong my midwife gave me a strap that when around the bottom of my bump then around my neck. did help.(no one seen it either as it was under clothes.)
hope this helps.