Fainting after blurry eyes and ears and a pain in the back of my chest

I woke up with a headache and a bad cough. I was feeling a bit "under the weather" but I thought it'd be OK.
For breakfast I had a little bit of chocolate cake with custard. It filled me up although I only had a very small slice. I have been eating cakes containing egg for over six months now, even though when I was younger I would have allergic reactions after eating cake (I would vomit and my asthma/eczema would get worse).
I was playing on a mobile phone for a couple of hours when I realised I needed to go to the toilet. Around this time I was beginning to feel hungry again. So I went to the toilet and after I got out I felt a weird pain in the back of my chest. It was a bit like stinging or burning in one spot on the left side of the middle of my back. I didn't tell anyone then because I didn't want to scare anyone.
I went to the room to sit down and suddenly my vision became blurry. I began to feel seriously ill. Soon after my hearing became blurry? too. My senses continued to deteriorate (I have never experienced this kind of thing before). I decided if I was to die I would die near my mother so I began to go towards the kitchen.
In the kitchen I told my mum that I couldn't see or hear properly. Then I believe I fainted (I don't remember falling but my mum says I fell to the floor after hitting the fridge). Then I regained consciousness, my mother gave me some water and milk and managed to get me up onto a chair. We decided not to call an ambulance cos i got better. After my sight and hearing returned to normal I began to shiver uncontrollably.
Because it was Christmas day I did not go to the GP (I believe the GP is closed on Chistmas day?). Now I don't know whether it will be worth it to go the next day - or even later (are GPs open on Boxing day?).
I'd really like to know because I've never fainted before and the episode of today has really freaked me out.
Thanks everybody, and please reply soon.

[Bridget A. Hewitt, RN]

Hi and thanks for using the forum.

I have a feeling that what happened is you had a drop in your blood sugar.  The cake makes your blood sugar spike high and then it dropped off leaving you with that fainting/tunnel vision/shaky feeling.  It would not hurt to see your GP when you can, just to be checked out and make sure that everything is OK.  For now, I would avoid sweets for breakfast and stick with something a little more substantial.  Good luck.

Bridget