Constructive criticism, you say? Allright.
Pros
++ Custom spriting. Everyone loves custom spriting.
+ The music was not annoying. This is important.
+ Environment damage. You could have done better, but you did well for your first flash.
Cons
- Reused dialog. It gets boring. Don't use it.
- Walking animation does not fit a 'dodge move'.
-- You need to enhance your VFX skills. Those static images looked lazy.
Well done. I look forward to you movies as you improve your skills.