in early pregnancy it is normal is what i hear but not all women get it though but the brown spotting would most likely be old blood and your body just might be trying to clean its self out. cramping like your period is normal but i think you should be checked out to make sure everything is fine hun.
I suggest u call ur Doc to make sure all is well...
Call ur Dr it can be nothing but u need to get checked out. I had the same problem and my Dr said to go in to just make sure everything was Okay. They did a Sono checked down in that area. I say go it never hurts to be checked out.
Don't be scared to talk to your Dr that's what their there for, and I'm sure he's heard it all. If your not comfortable with your Dr. You should find one you are comfortable with.
It's also happened to me, I had brown spotting, light cramps sometimes after sex there'd be a bit of blood, but I asked my Doctor about it and. He said as long as there are no Clots than its fine, and he didn't even prescribe anything, this spotting or light bleeding has a name I've just forgotten what's its called.
So don't stress much but do consult your Dr .