Suddenly hates bathtime! 😭

My baby is 16 weeks on Wednesday. He used to LOVE bathtime it was his favourite time of the day and all of a sudden he HATES it!!! He will go in the bath all happy and I’m able to wash him and then all of a sudden he will just scream out like he is in pain or something and hysterically cries until I take him out and then he is fine again, it is so strange, he has been doing this for a week now and I can’t work out what it is! Does anyone have any ideas or any tips as to how to get him to love it again?

Thanks! ☺️