Your shower head might be to blame for low water pressure. If there is a buildup of minerals, you're reducing the area that the water can flow through, and thus lowering your water pressure. To fix this, you can remove the shower head and use a pin to poke through all of the holes. Then, soak the showerhead in vinegar overnight to get rid of the minerals. Scrub it clean and replace it in your shower. You'll have better water pressure literally overnight.
Shower heads and bathroom faucets can be found at www.supplyhouse.com
