Less sleep

Hi ladies, is anyone else having the problem of waking up in the wee hours of the morning and not being able to fall asleep again for a couple hours?

I've been waking at about 4:30am, EVERY SINGLE MORNING for about a week and a half now. Then I can't get back to sleep until 7am. I'm currently 12 and a half weeks pregnant, and this is starting to get really annoying!

I thought less sleep didn't happen until third trimester? I have no problems falling asleep in the evenings as I've been taking magnesium and that seems to help a bit. It's just staying asleep... Any advice?