Memory,nauseous, and headaches

I had the Gamma Knife in July of 2011 and MVD June of 2013 MVD had some complications and still had headaches well now my headaches are better now down to one a day but in the past couple of months my surgery site and neck started hurting and alone with that I get nauseous. I cannot remember stuff. How to spell words even have came hard. I am now 17 and school has always came with ease but now it’s a struggle; it’s like I’m having to relearn things. My mom thinks it’s the medicines I’m taking but my medicines hadn’t changed when the symptoms started. After the symptoms started then my medicines changed-- added Zongran I believe is the name 200 mg at night. But I get nauseous with this new pain coming from my surgery place and sometime even feels like my head is just full and has pressure. Anybody else out there like this?

I only had my MVD a little over a month ago, but yes get headaches and sometimes my head gets hot and feels like my brain is pushing on my skull. I’m hoping this subsides as time goes on. I’m having a hard time communicating with ppl. I can see in my head what I need to say it just doesn’t come out that way.
Good luck with finding out why or if you can do something for it.