Erika, I’ve had achilles tendonitis for that’s lasted for years because of PT’s having no clue what to do. I finally came across this book, “Overcoming Tendonitis: A Systematic Approach to the Evidence-Based Treatment of Tendinopathy”, which has been really helpful and echo’s what Pete was saying earlier on this thread. It recommends isometric exercises first as they are less aggravating. It also recommends keeping a high volume of activity but replacing the aggravating activities with non-aggravating ones (like switching from running in hills to running on flat ground during recovery). It has a ton of other info too.
I have no ability to diagnose if you have tendonitis.