Stress effect on vision -reg below issue

Hello sir/madam, I have vision problem since two years, it is -.5 L and R even it is small compared others, I feeling not clear vision within one or two days after wearing new spectaculs. like this I changed 4 times my spectaculs in past 2 and half years. In last week I for severe headache continuously for 3 days and unable to see anything and i max time closed my eyes. I visited hospital, told power levels slightly changed and put some eyedrops after came out from hospital in sunlight I got flasshes white light with severe headache unable even open eyes for half an hour. I checked my vision 3 times in a span of one week i got different powers with slight variation of .25 and axis readings. Iam facing this problem also In sun light noise place and I have stress problem finally I thought it may b migraine? Help and give me some suggestions and at what stage am I? What may b the reason and plz clarify.. Thank you