This has happened twice in about 2 months. It will not stop filling up.

Of course I don't realize this until water is all over my bathroom floor (main floor laundry area). No matter what I do with the switches it will not stop unless I shut off the water valves. Then I can get it to drain and rinse etc, normally. I do reset the size switch b/c I read that would help to get it going again if it was stuck. I know that both times I had it set on the largest size. I don't know what water temp I had it set on the first time this happened. But this time I had it on cold/cold, but the weird thing is that the water all over the floor and in the washer was hot, not cold like I had it set.
Also, it was a couple months between these episodes. I read that it could be a stuck open fill valve. But why is it hot water filling it up? Please let me know if anyone has an answer, I really can't afford to have someone look at it. Thanks!!