New member, help with understanding test results

Hi there, I just joined this forum hoping that someone here can give me a little understanding about some test results I just got back.
When I went to me doctor about a week ago for my annual checkup I told him I was feeling ab normal, tired, no energy, muscle weakness, no middle of the night erections and just a general run down kind of feeling. The blood work he ordered for that visit all came back normal. I was thinking in the back of my mind it was low t, so I asked him about that he said it's possible but not too likely at my age, I'm 44. Anyway he agreed to send me for some more blood work, total test, free test, bio available and shbg levels. I just got the results back from quest, my doctor appointment to follow up those tests is next week.

Here are the results from quest diagnostics and the normal range:

total testosterone 685 range 250 to 1100 ng/dl
free testosterone 49.0 range 35-155 pg/ml
bio available test 98.6 range 110 - 575 ng/dl
sbhg 70 range 10 - 50 nmol/l

So my total test is ok, and even free test is in the normal range, but my bio available is low. Is that because the shbg is high? Is a low bio available testosterone level part of the cause of my symptoms? Is there a treatment for this imbalance?

Any help or advise would be greatly appreciated.