Editing Pleliminary film

Today in media our technician showed us how to edit our film on an application call final cut. After I understood how to edit the film we got into our groups and edited our task together. We found a few problems while editing. In the begining of the film you see oscar walking through a door and the cut there runs smoothly, but between the 2nd and 3rd cut, the cut was too short and needs to be extended. We he goes to sit down there is a black transition which doesn't make sense, that needs to be cut out and also we filmed an over the shoulder shot, and we realised that we should have more of the head in it because it doesn't look like the kind of shot we were going for. When making my real film I am going to try to ensure that we do not make any mistakes such as the onces we made in our pleliminary task.