So ds2 (2.5) was completely day toilet trained using a potty. No accidents, was taking himself. He'd been doing so well for a few weeks that I decided to try him on the big toilet. First couple of days were fine there too. He's a shorty so even with a step he needed my help to get on but there wasn't any issues. But over the last few days we have started having issues with the toilet. He's scared to go. He's holding his wee until he's basically busting, most we are still getting in the toilet but we've had a few accidents. Poo's he holds onto until he has a belly ache and can't hold onto them anymore. So many times he tells me he needs to go to the toilet and when we get there he says no and jumps straight off saying he doesn't need to go anymore. I don't know what caused it. We've had a few issues with him holding his doodle down on the big toilet and we had a number of pees that have ended up on the floor and although I told him it doesn't matter, he got upset with it. I don't know whether that's set it all off. I'm worried him holding on is going to make him ill, and I am worried by the increase of accidents, I thought he was doing so well and we have gone backwards. I asked him whether he wants to use the potty again, but no he refuses to do that to. He wants to go on the big toilet, until he sits there and then he no longer wants to go anymore. We were giving him a couple of m&m's when he went but that doesn't even seem to be enough of an incentive anymore.