A cramp in my cervix?

Marianne
I am so confused!  I am on my period now it is not like it normally is but not very light.  Then tonight I was just standing and I had this pain that felt like a cramp in my cervix?  I have never had this before even last month when I had a cp.  I don't know what it is, is it just a fluke?  Should I worry?  I didn't take a test after I started bleeding because I figured it was my period.