FYI I am a complete beginner when it comes to anything related to bikes. The other day I was trying to clean and lubricate my chain. Everything seemed fine but when I went to ride it the pedals wouldn't turn forward. I can backpedal fine, and when the rear wheel is lifted off the ground they can turn both directions. It seems like something about the pressure of the ground pushing up on the wheel prevents the cassette from turning forward.
I am getting ready to take it to a shop but I won't get a chance for a while and I thought I would try to figure out if there is a relatively simple solution (or at least figure out what I did!) first. My apologies if this kind of question has already been answered.