I couldn't get out of the inital screen at first, try making the singular objective more obvious. It took too many bullets to take that thing down. Maybe try circling it with a bright red, target symbol? I also ran out of ammo really quick on that third platform with the dino. You should slow down the non-human AI. In conclusion, I think this game has got real potential.
That dino should be carrying a human leg in its mouth!