KEEP GOING! Give it another week.
The origin of this treatment was a Swedish doctor/runner. His Achilles were killing him, and he wanted to get them operated on. Problem was that in Sweden (public health care), to get an operation in 6 months, it would need to be a full out rupture.
No worries, thought the doc...I'll rupture my tendon, recover from the operation and get back to running. So he worked out a cunning plan to rupture his Achilles. Sets of eccentric heel drops twice a day would do the trick.
Only one small problem with this plan. After two weeks the pain subsided. He decided to do some research to determine if this was a suitable treatment. Lo and behold, it wasn't just his Achilles that responded to this treatment.
The only word of caution I would give is that if you still have the pain in another week or so, check to see if you have neovascularization (like vericos veins around your tendon). If so, you are into an entirely different treatment.