I was sailing on my minecraft survival world and i wanted to check if my parrot was on my shoulder by checking my inventory. It wouldnt let me check whilst sitting in the boat, i got out and checked my inventory (he was there) i got kicked off the boat and started swimming,no biggy i could swim up, then when i exited my inventory the mouse was still there, maybe i had accidentally hit the help button had happened before, then the whole minecraft tab closed down. i got back on and it was like i had exited the world. I dont know why, but it seems to be fine again