Leg tightness/ feeling like bricks/ heavy/ dead feeling when running

Hello,
I used to be really good at running. It wasn’t until the beginning of 8th grade or even as early as 7th grade, (almost 3-4 years ago now), that I began to feel this tightness, feeling of bricks, heavy, dead feeling in my legs whenever I run. Its constant and rarely does this tightness fluctuate.
For some more context, I’ve been running regularly ever since the 4th grade. When this tightness started, I had been running in cross country since 6th grade. This tightness has haulted any significant improvement in my running even though I had been training regularly and running in meets. I went from running a 7:01 mile in 6th grade to a 7:28 mile in the 9th grade even with all my training. I will admit however, I have trained on and off ever since this tightness has started:
-Summer/Fall of 2019 (7th grade): Cross country, running 5 days a week for 20-45 mins
-Winter (2019- March 2020): Winter training, 3 days a week 2-3 miles
-Spring 2020: Virtual Track, training about 5 days a week with periodic time trials
-Summer/Fall 2020 (8th grade): Cross Country, 5 days a week for about 20-45 minutes
-Winter 2020: Swimming 5 days a week for 2-3 hours
-Spring 2021: Swimming and track. Swimming 5 days a week for 2-3 hours. Running 5 days a week for 20-45 mins
-1st half of Summer 2021 (Freshman year): Running 3-5 miles a day, 6 days a week
-2nd half of Summer 2021: Rarely ran. Last week of summer about a mile or 2 a day for 5 days a week.
-Fall 2021: Cross country, ran 2-5 miles a day, 6 days a week.
-Winter 2021: Winter training, ran 2-5 miles a day, 6 days a week with strengthening exercises.
-Spring 2022: Decided not to run track. Ran 3 days a week for 10-20 mins
-Summer 2022 (Sophomore year): No running, but was getting exercise by swimming, working in the yard, and cleaning
-Fall/Winter 2022-2023: No running, barely did anything. Ran here and there
-Spring 2023: Unified track running about 4 days a week really only doing sprints as this was all they offered in this program.
Now here we are. I’m contemplating rejoining cross country, but I want to figure out this leg thing before I do so. Cross coutry takes up so much of my time (its 6 days a week, for 3 hours a day).
I’ve been to a few doctors and both don’t know the issue. This issue makes me really unmotivated to run and I don’t know if I’m messing myself up by continuing to run with these weird symptoms. I’ve also tried physical theropy which did not help.
Other symptoms I have: I feel this tightness when I walk up the stairs and speed walk. Was tested for an iron deficiency in Spring 2022 to find that to not be an isssue. My mother has something simular to this, but her tightness gets worse the longer she runs (she is also no running nor athletic at all). She also has varicose veins (which are hereditary, but I don’t have them). I also get restless legs occasionally when trying to sleep (I may have Restless Legs Syndrome as well or this may just be some sort of side effect to my disease). These restless legs worsen the more active I am. I am also a female if that changes anything. This tightness is my whole leg and particularly effects my thighs the most. Again, the second I start to run, I feel this tightness. I also get drop foot and have actually fallen down once because of it. My drop foot seems to worsen (with daily activities) the more I run. I sprinted for 400 meters during a track meet last week. I suck at sprinting; long distance is my thing, but while I was sprinting I almost felt my legs going numb, like they were getting pricked all over. This has never happened to me, but again I barely ever sprint nor for that long. My legs are also always the first to give in during a run/race, never my lungs or breathing.
I hope someone can help me with this as I am tired of it. I’ve done a lot of research, but nothing seems to line up. I believe I have some sort of disease as it doesn’t seem to change at all based on my lifestyle. I stretch like crazy after a run and even again before bed just to be safe. If I don’t stretch after I run, my legs will be in unbearable pain even with just regular activities and laying down. I eat like garbage now, but when this started I will eating normally and healthy.
The closest disease I’ve found to my condition is Chronic Exertional Compartment Syndrome.
Thanks in advance!