I am sorry to hear that you are not feeling well, with weight loss and headaches. While it is possible that it is cancer, a number of other possibilities exist, and the best thing for you to do is to see a doctor and ask for a CT scan of the head and body. The main thing to keep in mind is that there have been many new treatments approved, including targeted therapy and immunotherapy - treatments that don't cause the traditional nausea, vomiting, and hair loss from chemotherapy. So if fear of cancer and its treatment is keeping you from acting, we'd encourage you to see a doctor and get this sorted out. It might not be cancer but still need treatment, or it may be cancer and be treatable too.
Either way, I think you'd benefit from seeing a doctor.
Aside from your doctor, if you haven't seen an oncologist recently, I would recommend making an appointment at Winship Cancer Institute of Emory University (https://winshipcancer.emory.edu/) or Mayo Clinic in Jacksonville, FL (https://www.mayoclinic.org/patient-visitor-guide/florida/campus-buildings-maps/mayo-building-hospital).
These are both top NCI accredited cancer centers, but are about 3 hours away.
If you want to go somewhere closer, I'd recommend seeing Dr. Tania Arora at Georgia Cancer Center (https://www.augustahealth.org/provider/tania-arora).
I hope this information helps and you are seen soon.