What Causes Migraine Followed By Peripheral Visual Distortions?

Had an "episode" yesterday a couple hours after having a small migraine headache or at least the peripheral visual distortions. Dream state, sub-conscious thoughts were "seemingly" invading my conscious, awake mind, uncontrollably, randomly and rapidly with fleeting thoughts as to their "reality". It was as though I had temporarily lost the gating mechanism dividing consciousness and dreams. It was fleeting, lasting only minutes but left me a bit confused and unable to think of names of some individuals I was to meet later in the evening. I feel fine today with little or no residual effects. Could this have been a TIA , something related to the sinus pressure I have been feeling, or something more nefarious?