Making my own Stop Motion Animation part 2

Now that I am nearly done with my animation I have ran into a few more difficulties that I feel should be shared. The first one being me having to go back and add in more frames to my animation. Now that may not seem like much work until you note that I named each frame I made as a number, meaning that when I went back to add more frames I had to change the name of all the frames after it. The scene that I wanted to change was the one shown below.

 After seeing it I decided that I wanted to show the shark fins swimming for a bit longer before I had them morph into something else, and after going back and adding more frames I got it to last as long as I wanted it to. After that I had to make sure that the new frames I drew matched up with the old ones; which proved to be a challenge but once I got it to look okay I was fairly happy with it. 

I am not yet done my animation but I am almost there, so you can expect to see it later on today.