Welcome to the club no one wants to join. Tongue cancer....notice how everyone's face changes when you say those words?

It gets better and so will you. Lots of great folks here who have been down this path. I had my cancer surgery/reconstruction and neck dissection in Oct. 23 and radiation/ chemo Dec/Jan 24.
So you're ready to manage your lymphedema. Learning that and practicing the self massage every day really helped me with healing and reducing my pain. Even now 2 years out I still have to keep on top of it. A few times it got the better of me and my surgeon prescribed massage therapy by an OT. So my recommendation is, if you need help ask for it.
I also wear a face compression wrap to reduce inflammation. It really feels good to keep the swelling down. Now I only wear it at night but it keeps my mouth closed so it helps with dry mouth.
Take care and be good to yourself.