Have you practiced with your hunting broadheads??

It is common for them to not hit the same as field points. You need to retune your bow for fixed heads or resight it.

If you do not bend at the waist - you can hit high up in a stand. If you bend at the waist and your form is good - your impact should be dead on.

You should always practice from a stand and with your broadheads - so there are no surprises in the woods.

Shooting at live animals is not the place to " find things out"