Installation Problem

So I run a YouTube channel, and I needed to download the trial for Final Cut Pro x. It said to install that I would need to upgrade to El Capitan. So I download it and tried installing it. I installed it at about 10:00 last night and as of right now its like 4/5 done, but it seems as if it is stuck. I'm not sure what to do. ANY FEEDBACK WOULD BE GREAT!