About 5 years ago I decided to remodel my shower . Long story short, I just got it done . My problem is I replaced the shower head and got a retro fit delta kit for the handle because I couldn't get the piece that's around the stem off. I had great water pressure 5 years ago , now just barely a trickle! Any ideas on what it could be. Everywhere else in house is fine. The house is 27 years old and it's the original handle! Help! I really want to get it finished!

There are several filter screens built into your new retrofit shower kit. They are there to protect fine spray openings in the shower head from clogging. Remove the shower kit and clean all filters. Run water w/o the kit installed to flush the system. Reinstall. That should help. Milo

Tried that!! Took head off and just ran the water , still just a trickle . Are there filters in the old handle itself maybe? I couldn't get the piece off that goes around the stem. There are plastic pieces around the inside of the stem ,do you think I need to take those out to get old handle off? Maybe filter inside?