Question about making fan trailers for Youtube.

Hey guys. I've been working on my own fanmade version for a Godzilla:Destroy All Monsters type trailer for several weeks now. I have some video and audio editing software that I haven't really learned how to use so I figured this would be kind of fun. However, I am using clips from about 15 different movies (including movie clips I own and found previously on Youtube) and also using a few soundtrack clips, once again found on Youtube. Oviously I am not looking to make money or anything, just looking to add to the fandom of the genre. I've read through the Youtube agreements for posting and I am still a little unsure about if it is safe and not get flagged. What do ya'll think? Or is there another alternavite for when I am done, to let you guys watch it.