As the others have said, it is common for symptoms to improve and then for things to go backwards, and you are still at a very early stage in the healing process…patience is definitely needed with this surgery! I understand how disheartening it is, it can be because the brain is adjusting to the new blood flow, it could be that swelling is still there and so compression has returned, and sometimes after surgery if you’re feeling better it’s easy to try to get back to normal, and to rush into more activity which can set healing back. If you have symptoms still from Lyme then maybe that could be contributing, I don’t know much about that but it sounds like there could be an overlap of symptoms, can Lyme disease flare up again?
There are some massage techniques which can help swelling if there is still some:
How to do Lymphatic Self-Massage on Your Face, Head and Neck
Scar /wound healing tips please - General - Living with Eagle
@carina has had surgery not that long ago, and was still getting headaches, but I think things are finally improving for her, here’s a link to her discussion:
4 Weeks Post Op and Still Feeling Worse than Before - General - Living with Eagle
If you scroll down to post 32/37 she mentions some improvement so hopefully that will encourage you.
As the others have said too if both sides are compressed then you may need to have a surgery on the other side to see a bigger improvement…