Knee Tendonitis from Cheerleading

Hi, I’m a fourteen year old girl cheering on my high school’s varsity squad.
When practice started, my knee began bothering me a lot and I went to the trainer and he told me that there were no ligament/tendon problems so I shouldn’t worry.
It continued and gradually grew worse, so I talked to my mom and she (who has extensive experience in the medical area but lacks a medical degree) determined it to be tendonitis.
The school RN agreed with her.
I have been wearing a closed patella ACE brand brace and icing it after practice every day for 20 minutes. Am I doing these things right? Or would an open patella brace work better? The pain is right below my knee cap, on the tendon that joins the kneecap with the shin.
Thanks for your time and help.~Cami