What if I don't know what's wrong with my back but it hurts?

First try the techniques in the video, and see if your lower back pain resolves. If not, then this could be why you still have lower back pain:

You could have kidney stones. They often occur only on one side. You can get them if you’re consuming a lot of spinach and nuts, and not drinking enough lemon juice in water. An excellent remedy for either oxalate stones or uric acid stones is hydroxy-citrate. I don’t recommend any particular brand, but you can research it yourself. It’s a very powerful compound that helps dissolve stones. I believe it’s more effective than potassium citrate.

To prevent kidney stones, drink lemon juice in your water. Apple cider vinegar is another good remedy.

You could have endometriosis, which is excess tissues growing in your abdomen. There’s a high level of estrogen involved. You could have fibroids, which is also a condition of estrogen dominance, or ovarian cysts. Another possibility is poly cystic ovarian syndrome (PCOS), which is a condition of high levels of androgens. If you have any of these, increase your intake of cruciferous vegetables, eliminate dairy, increase your intake of sea kelp, and do intermittent fasting.

You also want to go low carb if you have PCOS. High carbs increase your insulin, which in turn increases your androgens. In other words, do healthy keto.

You may have an enlarged prostate, in which case do keto and intermittent fasting, but also avoid dairy.

Repetitive exercises may also be the cause of your lower back pain. If possible, reverse the direction of the exercise to balance it out. If you’re a cyclist, the muscles you build up in your legs can throw off your lower back.

Finally, you may be sitting too much! Get a foam roller and put it under your back to create the arch it needs.