Constant, low ache?

MrsJ723

I've been having some cramping on and off since my bfp, which I had with DS and know is fairly routine, but today started a more continuous, low ache. Mostly dull, but at times a little sharp.  It's concentrated right below the bikini line in the center, whereas my cramping as been more similiar to AF cramping (spread along my lower abdomen). Just wondering if anyone has experienced something like this?  I'm sure it's nothing, but sometimes it's hard not to worry.