Lovely colors, and I just want to make some funny comment like "oh did you mean spinenosaurus" but oh my bad, I mistook the back fin for it's back, and it was actually quite accurate drawing too, (my bad for not understanding Dino's proportions). Great job friend, and welcome to Pixel Joint 

 

hope to see more of your drawing.

 

oh and you might need some cleaning, there some random color that don't have any purpose in it.

hover your mouse pointer on the lower color, it will show the number that color is used in your drawing, some of it only have 1 pixel in your whole drawing, I recommend you delete the color or replace it with the color you have more in the drawing to lower your color count, it was optional in this drawing but it was good practice, to clean up your drawing.