I don't know if it's contraction or not

Mrs.
I have been feeling like I'm on my period and when I sat down it let off but now it's coming back on and off and they are kinda painful! My discharge went from kinda thick to very watery and a lot! My stool has gotten very soft and I have to go a lot more then normal! My daughter is kicking a lot so I'm not worried about her but it's kinda painful! What do you guys think?! I'm only 28 weeks today!