First time mom, need help with baby fussiness or is it something else?!!

I have been struggling with my babies fussiness for a little while now. He’s 12weeks old and I have never seen him do this before. When I feed him and burp him, he will be normal and content but as soon as I put him down he starts like making some noises (like if he’s pushing to poop), he would also wake fall asleep making this noises and he would tilt his body to one side… I have helped him with stomach massages and I also give him Gripe Water (don’t know if it helps) he will fall asleep, not by his own because he doesn’t fall asleep if I don’t have him on me. I don’t know what else to do!! Should I be concerned about this ?!!