Toddler in very bad mood 😫

Hi everyone since a few days my son is not the same as always , he is crying most of the time , he wants to be carry all day and is little hard because he is 12 kilos and he don't let me do nothing. We believe he is teething with the last teeth because he is so irritating, with averything he go crazy crying. We buy one teething relief gel but it looks is not working. Any idea 💡 what can be happening? He is good no fever no dirrhea , only I see he is eating less than usually.