I haven't had my period in six months. I'm not sure if I'm ovulating either. Does this mean I just can't get pregnant now or does it mean illness?

If you are sure. you are not pregnant (after checking pregnancy tests twice 1 week apart), then you need to see a physician or healthcare provider for diagnosis and treatment. If you are pregnant that would explain your lack of menstruation. If you are not, then it could mean many things but hormone problems are at the root of it.