Nope, the pressure is governed by the distance between the cold water cistern in the loft and the height of the shower head. Regardless of whether the pipe supplying the shower rises first (unless it rises above the level of the cistern of course) That being said the more bends, tees and elbows it has to negotiate, the less flow there will be at the shower.
Your bath taps are probably full flow screw down type with 22mm feeds? The pressure will still be rubbish but the flow will be great.
Is it a modern bar shower that you have and a rain shower head? If so that'll be your major restriction to slowing down the flow. You'll need to consider a pump but you won't be able to pump it the way it is at the moment, to much air liable to enter the pump. You could look at a power shower.
Your bath taps are probably full flow screw down type with 22mm feeds? The pressure will still be rubbish but the flow will be great.
Is it a modern bar shower that you have and a rain shower head? If so that'll be your major restriction to slowing down the flow. You'll need to consider a pump but you won't be able to pump it the way it is at the moment, to much air liable to enter the pump. You could look at a power shower.