Earlier today/This morning I was in Mc'Donalds with two of my friends... I went and stood in the que and my friend joined me in the que seconds later. It was quite busy and there were people in front of us. Seconds later after my friend joined my eyes were gradually going black until eventually I had no sight at all!!!! 

I could still hear and my friend kept telling me to stand up straight and be normal, however it's easier said then done. Honestly I could not see at all and I was freakish out. 

My friend was calling my other friend to come and get me and she took me to the toilets. When we were in the toilets I had to sit on the floor and my sight gradually came back. 

I continued sitting on the floor while my friend got me a drink and my head was spinning like mad. 

Im not quite sure how long I was in there but my friend got me up and said we need to go and asked if I was ok. 

When I fully had my sight back I went into the que so I could get my food and my friends came with me. I was next in que and I was talking to my friends and again suddenly my eyes went black, I held on to my friend. That one only lasted about 30 seconds however it still felt terrible. 

After all of this my friend told me that my eyes were wide open and she thought I was joking at first however that is one of the worst experiences I've ever had.

Does anyone know what it might have been? 

I kind of longed that out a bit sorry.

It'll be much appreciated if anyone knew as replied back. Thankyou so much x