I know, the last 3 months have been like that for me. While trying to get ready for the start of the season (which is in 7 days for me) I thought it would be a good idea to do physical instructors course to help out at work. The course went for 2 weeks where we were shown and took circuits classes and resistance training. Doesn't sound so bad.... after 2 days of intense circuits - 12 x 15mins circuits back to back - my ankle wasn't liking me too much. Turns out that because 99% of my training is done in one plain - forward and back - I wasn't used to doing a lot of agility work and developed crepidus in my left Achilles. Best explained crepidus is an inflammation of the sheath that surrounds the muscle, along with a lot of fluid build up felt like I had a cheese grater in my ankle. Needless to say it wasn't much fun and it put me behind the 8ball massively in my running.
I have had this problem before in my right ankle so I thought no dramas, I'll just do what i did last time and it'll be gone in no time...WRONG. It took 3 months to get it to a point where the fluid is slowly going and the cheese grater has gone. I had an ultrasound to make sure there was nothing major wrong and thankfully there wasn't. I just had to continue with physio, a lot of ice packs, wrapping my ankle in glad wrap with DOMOSO ( check it out good stuff), run in the pool for 2 months and then try to manage my training accordingly, which can be very frustrating indeed.
From all of this I have learned a few things - 1. Don't stop training completely, just modify it to minimise the pain and to a point where it won't inflame it, 2. See a physio, chiro, massage ASAP and continue with 3. Google the shit out of your problem, because there is always someone out there that has had the same problem as you but might have tried something slightly different that might be worth giving a go.