vaginapagina | Period funkyness...

Hello ladies! I'm experiencing a bit of oddness with my period. I had it last in mid-December, so I'm due, and the past few days, I've been experiencing cramps, but they're more like how I imagine contractions would feel. It starts, builds, and tapers off, maybe twice every five minutes or so. Normally my cramps are constant pain. Is this just a new symptom, or could I be pregnant and somehow miscarrying (as I'm sexually active, but there's very little chance I could be pregnant, as my boyfriend and I use protection, and we clean up pretty quickly if he finishes on my body)? I've been having all the usual pre-period symptoms, from my left breast swelling to slight emotional issues to slight acne breakouts. The cramps are just funky and it's sort of bothering me. Thanks in advance!