Achilles tendonitis

Last July my achilles tendon basically froze up and each morning I would have to learn to walk or limp. It would loosen during the day. I had a job that would not allow any rest and by December there was no improvement. In February of this year an orthopedic put me in a boot for 6 weeks and I have been taking advil. June and I am maybe 50% improved. I have a very hard nodule on the back of my ankle. I am massaging the tendon but the size of the nodule is not changing. I was reading that you can get a buildup of mucoid is that what I am feeling and does it have to be removed sugically? Thanks for any help or suggestions. I am 54 and initially injured both tendons in 1985.