Lately my horse has decided that he was going to do his own thing and ignore what I ask of him under saddle, especially if it involves turning to the right, or even going forward at all in certain parts of the arena and pasture. acting up is very very unlike him. I decided to rule in/out any pain issues. checked his legs, back, withers, neck, but came to a halt when I got to his mouth. A few days ago I asked my brother if Samson's mouth looked a bit swollen to him, but it was hard to tell, so we just waited (stupid, I know). Anyway, I went out for a morning ride as usual, and as I said before, he was being a completely different horse. Backing up when he was asked forward, not turning when he was asked to turn, not speeding up when he as asked to speed up (I'm an experienced rider, so its not like I don't know how to ask these things from him lol). I've been using the same bit, but I always used to complain that it was a little too large for him. I brought him back to the barn to, as mentioned before, check him over. The bit that was a smidge too large for him was now too small, with no room to spare on the outside like there usually is! I did also notice a tiny bit of clear discharge coming from his nostrils when I put the bit into his mouth. and small noises coming from his nose when I was riding, not usual horse noses, but it almost sounded like soft snoring (if that makes any sense)? Someone please help me find out what the problem is, and what I should do about it!