I don't really remember mine but my mum is an emetophobe too, when I was little and used to V she couldn't bring herself to comfort me and was a single parent so I was left to deal with it alone while she literally hid around the corner shaking with her hands over her ears, so I basically associated it as a bad thing all my life. I also got FP while on holiday when I was 7 and V'd almost constantly for the full 2 weeks, alone in the small hotel room bathroom while my mum hid and I guess that scared me not even having the comfort of my own home, just my trusty teddy!
I realised I had the phobia when I was about 10/11, I hadn't V'd since the holiday incident (or maybe just once since) I remember really clearly having a chocolate milkshake and suddenly feeling really N and in that moment I started shaking and crying and panicking as I didn't want to v, it was so scary, from that moment I literally didn't leave my bedroom for about 6 weeks (it was the school holidays in summer) as I was so worried that feeling would come over me again, I ended up in emergency therapy as I wouldn't attend school when it came back around of fear of feeling n and getting sick.... As it happens I didn't v at all until just two years ago. I panicked loads but I really really wanted somebody to be with me and hold my hand and reassure me, so I guess my experiences of being alone did have a big impact! Hmph hate this phobia!!