If blood work and neurology reports came back normal, no ct scan, but my physician looked at optic nerve and full examination he doesn't suspect brain tumor, am i safe?

Probably: But it would depend on the symptoms you are having as to whether further workup needs to be done. This could include a ct or an MRI of the head.

No: It is definitely possible to have a normal neurological examination and no changes in the optic nerve head as viewed with an ophthalmoscope and still have a brain tumor. It is, perhaps, unlikely, but not impossible. The best test to exclude (or find) a brain tumor is an mri.