Still have a fever

I am still maintaining a low-grade fever. The range is only between 99 and 100 but it is enough to make me feel horrible. And the fact that I have had the fever since the 6th of October has me worried. It is odd that when I rest I don't have a fever, but when I am up and active, my temp spikes. I usually can tell because I start to feel drained of energy and feel all around bad. I hope that after surgery, since the mass will be gone, my fever will diminish and I will be back to normal.

I am worried because the fever has lasted so long.

A week is long enough but I am pushing three weeks now.