clearly something isn't working. Stop posting about it and figure it out. Work on your mechanics, lift weights, get stronger. Train with a purpose instead of hoping you get faster by running more.
get bloodwork. could be anemia(low iron levels). take iron twice per day. I had a runner go from 30 min 8k to 24 min 8k in under a year after doing this.
If you are running those times with mileage up to 50 pw, then I can say that you almost definitely need to do some speed work. Bring the mileage down slightly, and run one or two high intensity workouts with the remainder at very easy/recovery pace. Make sure you are well rested and fueled for the workouts. find a track and run some workouts with 400s, 800s, ladders.
1. lose weight. I know it's kinda taboo these days but dropping 8-10 lbs will do wonders.
2. get a coach, find a good coach in your area and just turn off your brain and do what he/she says. even one of the local HS coaches will usually be happy to help if you slide them some ca$h for their time.