Actually testosterone and other androgens have a negative overall effect on tendons. Reduces elasticity, increased fibrosis, increased rate of rupture, etc. Natural levels of testosterone/DHT are going to be fine, but these hormones definitely aren't healing tendons.
Estrogen actually helps tendons by increasing elasticity. However, estrogen is also associated with small tendon diameter, so it's a big give and take.
Growth hormone also helps heal tendons. Growth hormone is naturally occurring (no peptides necessary) and there are ways to raise it naturally, such as getting better/longer sleep, eating a healthy diet full of healthy fats and strength training.
The best thing for tendon health is going to be steadily increasing the loads you're using when strength training, eating a good diet and sleeping well. Period.
There are no magic bullets when it comes to this stuff.
Go see a doctor for sure and have them check for hernia/disc herniations.
How is your flexibility btw? I had hurt my lower back a few years ago deadlifting and, believe it or not, regular old static stretching of my hamstrings/calves/hip flexors helped out IMMENSELY. Previously I had been unable to deadlift without getting a massive back pump and stiffness/pain. Now I can deadlift, bent over row, etc. all I want without any problems.