I also happen to be in my 12th week.
If there's no bleeding I wouldn't worry to much. It's probably just your body stretching out. You're probably just experiencing symptoms more this time don't worry as much as the sickness sucks it often means healthy baby. If you're really worried consult your doctor at your next appointment.
It sounds like round ligament pains. If it becomes unbearable or if you start spotting call your Dr right away.
I second the round ligament pain. I had it something awful with my first and no matter how many people told me it was normal it still freaked me out lol. It got worse around 20 weeks and stuff, btw, became super paranoid because I was like, what does early labor feel like? Lol Just know that it's normal unless you get severe cramping or bleeding. Your organ is growing huge and moving up into your abdomen and it WILL kinda hurt lol