Suddenly fussy

Angela • God, Wife💍, mother🤱🏾👶🏻👧🏻🧑🏽‍🦱, 👩🏾‍💼accountant manager, aunt of 11
So my now 16 week old is suddenly getting fussy and not sleeping like he usually would. My mom said it's most likely teething. He only wants me and he'll accept his father for a few minutes before he cries. He hasn't really been eating normally either. He has a doctors appointment coming up soon, but I'd figure I'd ask some moms.