Oh, yikes! Talk about bringing back memories. I had a brush with sleepwalking around a year or two ago and it was an absolute nightmare. Lock all the doors to your bedroom, first off, and take anything out of there that you could cause damage with. Put a padlock on there if you've got to and give your boyfriend the key so you don't just sleepwalk to its location to retrieve it. If the phone is in your room, it also might be worth unplugging it. I know this sounds wickedly drastic but if you nearly lit up you could seriously hurt yourself. It took me waking up in the shower with it running to take the same step. Death by drowning in the shower = lame.
I'm sure your doctor will have some ideas on why and perscribe you a sleeping pill for a week, at the very least, so you restabilize. In the mean time, have you changed your diet recently, or had anything traumatic happen? You'd be surprised what can mess up a person's body. If you've got an allergy to something it could be doing all this! Crazy, yeah? Retrace your steps. It very well could solve the problem.