8 Weeks Cramps/Back Ache

I’ve been having cramps and back aches, and pressure as if my period is coming, currently 8 weeks 5 days pregnant.

Is this normal? Earlier today I thought there was a tiny bit of brown color on the toilet paper but it was so small I wasn’t sure. Other than that no spotting or bleeding, just the cramps that remind me of when my period would come.

Yesterday was my second missed period, but I really feel like it could come at any moment.