Hmm, curious. The main symptom of bursitis is pain. You say you cannot recall an injury, but a few days ago you did report pain from a workout - did you tell that to the doc? It would qualify as an injury. But at least he doesn't seem worried about a serious disease or condition.
Also, having a muscle look "flabby" when lying down is pretty normal - that is its relaxed state, and not an indication of a problem.
What did the doctor recommend? The usual treatment for bursitis is range of motion exercises coupled with low-impact aerobic exercise such as walking, biking or swimming to improve strength. Any weight training for that leg should be limited to moderate weights and reps. If doing these consistently (ie 5-7 times a week) for a few weeks doesn't help, it would be time for more exploration. Also, if the leg gets so weak it begins to buckle or not support your weight, see the doc.
Let us know how you're doing in a week or two.
Sue

Hello, I see this was posted in 2021. Have you had any issues since? How are you doing now?