Cancer?

So I really feel like something is off with me. I have not been really hungry, I feel sick, tired, my arm is so sore. This has been going on for weeks. I fear cancer, I seen my mom go through it and it terrified me. Now I did how blood work done by my doctor and everything looked good, now if I did have cancer they would have seen that by my white blood cells right? Im in the process of getting on insurance because we had to switch.. idk what to do, I have a genetic testing next week because I have history of cancer on both sides....