Here's what actually happened when your doctor said you're fine:
He checked your total testosterone. It was technically “in range.” Case closed.
But total testosterone is like your gross paycheck. $6,000 a month sounds decent on paper - until rent, bills, taxes, and groceries eat up $5,700. What you actually live on is the $300 left in your account.
Your total testosterone = the $6,000 gross paycheck. Your free testosterone - the part your body can actually use for energy, drive, muscle, and mood - is what you're really living on.
And that number isn't locked by age. It's heavily shaped by how you sleep, train, eat, and handle stress.
You're not declining. You're uninformed. There's a difference. And it's a fixable one.