When I had low T...I couldn't really tell. I was young (23) when it happened. My TT was 299 which is higher than yours, but keep in mind I was 23 so I feel I would be more effected by a level like that because I should be used to high levels. The best way to describe it was just an overall feeling of nothing. Nothing excited me, nothing made me sad or mad, nothing effected me mentally or emotionally at all. I just loved to sit around and turn my brain off and stare at a TV. I couldn't be bothered with going out or being social, talking to girls, nothing. I wasn't sad or depressed, I was just empty. I had no drive, no spark, no interest in doing anything but sulking. I just couldn't understand other peoples' energy, motivation to go out and hang out with friends.
It wasn't until I started trt that I realized just how bad I was. Within 3 weeks I was noticing more energy and motivation. I wanted to explore life, meet people, better myself. I hate sitting around now. The world has a new color to it, a new brightness. Things have meaning again. My libido was non-existent and now I'm like a teenager again.