Rothmaninc - the anhedonia hung on for me for a long time. So long that when I started to not feel it it was like a surprise to me. Like I was like "oh am I feeling excited about going out to see a movie and I'm not just forcing myself to do it?" That lasted for me well into 18 months and during waves in my second year. It'll come back.
I also had tons of GI problems and if I have a wave even now I'll have what you're describing - the back and forth between extremes. Remember that your whole GI is nerve tissue, and it's healing just like your brain. I knew I was getting better when I could eat certain foods again and just have some peace in my digestive tract. This also took more than 18 months - more like 2 years.
Anxiety was just a chronic constant for me, but I'd find I'd have outbursts of irritability and anger - I think it was PAWS but also just general frustration with being "this way" for so long. I think you get a little resigned to it at times.
Heat intolerance - I was really really sensitive to sunlight, and would find myself happy when it was a rainy day so that I wasn't overstimulated by the sun. I had a very hard time regulating my hot and coldness in my body, too, and if I got too hot I'd be sort of freaked out - I'm not sure if that's what you're describing.