usually after doing any kind of effort i feel lower back pain and sometimes uterus and ovaries pain and sometimes slight cramps in the lower abdominal part i'm also 8 weeks preggo ,, i told the doc he told me that its ok coz my uterus is stretching and that i should start worrying if the pain is severe unbearable or if i started spotting or frequent and severe cramps ..so dont worry we all do experience the same ,,, but try to rest dont carry heavy stuff dont jump off the bed no hot tub :( avoid stress
best of luck :)
i've had lots of weird back and pelvic pain with this pregnancy -- its normal for some women. try to relax and not stress about it. of course if you get spotting go to the dr or ER but it truly could be just normal and your body adjusting and stretching as your uterus grow. congrats!
Just realize that your body is going through changes, muscles are streching, balance is different and overall your body is adjusting to what it needs to do to carry a baby. With that being said it is easier to strain or pull muscles especially in the back because a lot of strain is put on it during pregnanancy. Just be careful and don't over do it.