How to overcome plantar fasciitis...

Hello ^^
I've been running steadily for about two years, so I lost a lot of weight and really saw the benefits of exercise.
Since I'm not exactly young, it bothered me when people said I looked a bit old...
So lately, I've been refraining from running and spending my time at the gym doing light workouts and bathing.
But now, the soles of my feet hurt, and I feel a sharp, stinging sensation every time I step down.
When it gets bad, I even limp.
Thinking I couldn't go on like this, I went to an orthopedic clinic, and they said it's "plantar fasciitis."
They told me to try taking medication for a few days, and if there's no improvement, I'll need to get injections.
I suspect that my habit of enjoying walking, combined with wearing shoes without cushioning, played a part.
I searched on YouTube and found various stretching methods;
I've tried following them and even doing foot baths, which seems to have helped a little,
but my heel still hurts when I walk, and it hurts even more when I walk for a long time.
Looking at the sole of my foot, it feels like the arch has become a bit flatter. T_T
Has anyone here successfully fully recovered from plantar fasciitis? Please share your methods.
I'm going to try a bit more on my own before deciding whether to go back to the hospital.