Some background to this: my son started doing water confidence classes in September last year. Took to them really well, really enjoyed them and was very confident in the water. We switched over to a new class in July as we didn't feel like he was progressing to actual swimming in his previous ones - he did a few sessions at the new place and thrived - really enjoyed them, told me he preferred the new classes to the old ones, and even started being able to swim without any floats which he'd never done and was really proud of himself! Then, all of a sudden out of nowhere, we went to the lesson and he spent the entire class sobbing in the pool and crying for me. We were then away and missed the next class, but went back again today and it was the same - crying and crying and refusing to do any of the lesson. He can't tell me what the problem is and just says he was nervous and couldn't calm down but won't tell me what was making him nervous.
Any advice? Our stance is that learning to swim is non negotiable, but equally he's not learning anything if he's just clinging to the edge of the pool and crying. It's very frustrating because it seems to have come out of absolutely nowhere and we have no idea how to get past it!