Nausea 8 months in?

Hi all!

I been on lamotrigine for 8 months and been doing well on 150mg for quite some time. I haven’t had any side effects other than a few months ago when I went from 100mg to 150mg. I’ve pretty much been living my life and taking it every evening. All of a sudden Ive started waking up w/ nausea out of nowhere. I thought it was a new pms symptom, but nope still happening. Has anyone ever had this happen? Makes me so upset because I’ve been doing so well on it, aside from the memory issue and a little blurried vision I haven’t been experiencing overwhelming sadness like before.