Would a Brain MRI without Contrast & a CT Scan with and without Contrast show a brain tumor causing symptoms? Worried that it could have been missed.

No symptomatic tumor. It is a pretty safe bet that MRI together with contrast CT can exclude a symptomatic tumor (mass) in the head. That does not mean all causes of headache or neurologic complaint are seen. Only your practitioner can give more advice to "put your mind at ease" and further direct your diagnostic journey.