Carrying very low? Is it okay??

Amber
I am 28 weeks and 2 days pregnant with my first child. Since I started getting a baby bump he was always low, but the past couple weeks he has been very low! And I am so uncomfortable ! I can't sleep at night because I can't get comfy, so many pains and back pain I guess because he's so low. I am always having spasms in my stomach the past week ( which i don't know what that is). Is it okay to be carrying low or should I contact my doctor ? I'm having an ultrasound Monday but I didn't know if that would tell me anything ! Does anyone have tips for me or advice to what I could do? And also answer my question of does it mean I can go into labor early?