@nicoleen1973- Hi. I am not familiar with back surgery. The location may or may not matter. What matters more is that surgery itself puts enormous stress and shock on the body. It is all connected. The back is not separate from the rest of the body. Only surgeons put body parts into separate categories.
When the body is stressed from a surgery , this can have a cascade on the physical/emotional. Immune system can lower, making more susceptible to all kinds of things. One thing with back surgery, if you are not moving around like normal. Laying down a lot. This can cause upper respiratory congestion/infection. Are you moving as much as possible. Drinking plenty of fluids? Hydrating?
Have you had the right support, healing afterwards? Such as proper restoration of vitamins/minerals and nutrients. Body movement and social interaction?
Healing in itself can be exhausting. It is very normal if you don’t feel you are healing properly or have a new issue, as a result of surgery to feel extremely fatigued and nervous. I recommend working with someone who can help calm your nervous system and make sure you are getting adequate sleep and healing nutrients. Once a surgeon is done with his surgery he/she is pretty much no help when it comes to complaints. And seeing more doctors for tests that come back normal can cause you to feel worse. Trust yourself first. Don’t allow doctors to let you think it’s all in head.