Its not going to get any better. At 313, you are at the bottom of the acceptable range. I'm on TRT for life and its the best thing I ever did. However, its for LIFE or until I get old enough not to care anymore I guess. If you go down this road, there's no gettng off.
At 51 my libido is out of this world, body fat is low, attitude is great, etc. I do have to give blood every 8 weeks to keep my hemocrit down but that's about it.
Make sure your Dr is ready to give you an anti-estrogen or you will feel worse than you do now. Ask to be allowed to do self injections, make sure you inject every 3 days or so to prevent peaks and valleys in your test levels.