Back pain so bad it felt like contractions.

Anyone else had this happen? I'm pretty big chested naturally,(34 J after my first pregnancy, and now about a K) so I'm used to back pain when wearing a bra, especially since I have scoliosis right between my shoulder blades. Today though I had such horrible pain in my mid back that I actually felt like I was having full on contractions. The only thing that kept me from freaking out was that there was no tightening of my belly. I swear this pregnancy is trying to cement my decision that two is enough and to get my tubes tied. Between pelvic pain, back pain, and just general exhaustion, I'm done. Can it be January yet?