Onset: Some afflictions have a variable amount of time before they set in. Creatures that come in contact with an affliction with an onset time must make a saving throw immediately. Success means that the affliction is avoided and no further saving throws must be made. Failure means that the creature has contracted the affliction and must begin making additional saves after the onset period has elapsed. The affliction's effect does not occur until after the onset period has elapsed and then only if further saving throws are failed.
it seems like you are diseased but it is not doing anything yet. if you can tell you have it then I would say you can cure the disease before it starts doing its thing.
The heal skill does not recognize diseases, but in my games I would allow it.
Only mentioning this because we are in the rules section.
I would make that more a Profession (physician) check. Or at least decrease the DC for a physician against someone using the healing skill.
The heal skill seem a mix between the abilities of a nurse and a field chirurgeon, not a full physician.
Note that in my current games I am using the background skills, so it is common to have a decent number of skill points.