How much cramping is normal?

[kimmy04]

I should know this by now as I remember some minor cramping each pregnancy! I'm on baby number 3 and pregnancy number 4. I'm so early and only just found out, but of course for days I was waiting and waiting for AF to come because I was so sure she was on her way. Now that I know she's not coming I am still constantly worried because it feels like really bad period cramps and I keep going to the bathroom expecting to see blood! I remember cramping every other time as well but I had a late missed miscarriage in 2014 so now im paranoid.

How long does the cramping stage last? And is cramping all the time normal? It just feels the same as period cramps.