Do you think you might have unresolved issues? For me, I was underweight and not as emotional as I was before when I weighed 15 lbs or more. When I was very thin, I was unhappy that I had no muscle so I started eating more to gain muscle mass and then stumbled upon this low metabolism stuff…. I have gained about 25 to 30lbs and have become much more emotional but I have a lot of crap to work through – crap I was able to ignore when underweight because I don’t think I was present in some ways.
I think when weight goes up – hormones are going to also and fluctuate, and when that happens emotions can emerge stronger – especially if there are things happening that seem negative and you don’t have resilience.
As far as still being exhausted – are you getting enough sleep? Maybe you need to increase that, though I know that is very hard to do sometimes. Sometimes stress can make our extremities feel warmer but our basal temp is still low. Do you know if you temps are actually up?
Even though I don’t think I am physically stressed – I have a lot of negative thoughts and emotions and so I must be in a stressed state and think I should learn meditation, yoga or something… It is may seem simple to increase the starch, salt and sugar components of the S’s but increasing sleep and managing stress can be tough…