This condition might indicate orthostatic hypotension which is unlikely to happen in your age..
Given that you haven't mentioned about any comorbidities any history of drug intake or any familial disorder ,it is difficult to reach to any provisional or differential diagnosis. So it is better that you should consult an ophthalmologist and a neurologist at the earliest
Next Steps
consult an ophthalmologist and a neurologist at the earliest
Health Tips
This condition is serious and deal it with caution. Do not suddenly start walking and standing once when you wake up from lying posture. give some time.