How did lithium toxicity manifest in you?

I've been having some issues lately that I thought might be a depressive episode, but something feels off about it. I've been really overwhelmed, anxious, agitated easily, and just flat out exhausted lately for no reason. Generally just feeling a bit ill inside and strange. It's like there's something under my skin and I need to tear it open for it to come to the surface (metaphorically, and NOT in a psychosis way).

I have an appointment booked in on Friday to see my GP about it, but am considering calling off the only shift I have this week and going.

I'm not really asking if this sounds like I have lithium toxicity or not, but I was wondering what it looked like when you guys had it?

I'm on 750mg at a blood level of 0.6 when I last checked.