swelling of groin lymph glands

I am a 52 year old female who has been in a training program for about a month. My goal was for toning but was given the same weight program as the group. Yesterday I noticed a nodule (pain when touched) in my left groin area. Was seen by a dr today and discovered inflammed area on both sides of my groin. Was put on an antibiotics for 7 days, warms baths and light exercise until a follow-up next week. Could this be from the strenuous exercise? Really not eating correcting (lost 5 lbs) and with the holidays probably a little run-down.