I'm 4w2d pregnant. Had 2 misscariages before. I have cramps and backachs that killing me. I also have sleeplessness. Should I worry? .What can I do?

Worry won't help. It's normal that you are worried. Misscairrages are emotionally difficult at any stage. Right now the best thing you can do for yourself and your pregnancy is find ways to care for yourself emotionally and physically. Go to your scheduled check ups, if you have another misscairrage see what's going on physically. Worrying about this pregnancy at this point won't help. Good luck!
Get to the Doctor. These are not healthy signs or symptoms of pregnancy. They sound like infection. Please for you and your baby's sake, sign off of the internet and get to the doctor's office today.