Lake monster help????!?

Ok, so me and my friend went kiaking and we were in a lake but it looked kind of like a river and it was a little away from her house so we were terrified of alligators cuz we kept seeing splashing and stuff and we eptk seeing bubbles soooooooo.. when we were kiaking i was a little ahead of heard and she wa like omg turn around now we are going back!!!!! so when we were trying to paddle away fast she told me tha it has a round head and a pionted head at the bottom ind of like a beak and it was a grey green and she sad it ut sared at us then when under and its snake like body went like in an arc adn disapeared...its scary help!