The tiller looks great to me - that's not the issue. I also don't think the bow is too long. The tips do seem a little bit on the heavy side. The overlay could be half as thick, and the tips are also a bit too wide. Nothing extreme, but I'm sure shaving down those tips will help.
What weight are your arrows? You should be shooting between 8 and 12 grains per pound drawweight. Arrows that are underweight will increase handshock.
By the way, what's that black stuff on the back? Is it just paint or something else?