Would there be any sign of a slow brain bleed on initial cat scan if bleeding starts later, would i haveany symptoms?

Consider followup: Not all intracranial bleeds are seen with the first ct. If you have signs, symptoms, or history to suggest that possibility you should see a doctor and possibly get another ct scan. The history you provide is not specific enough to give you more information.

Spinal Tap?: Some minimal bleeds will not show up on ct and might require a lumbar puncture (spinal tap) for diagnosis. This is done in the presence of compelling symptoms even with a negative ct.