<human>: So we went out shopping today to pick a few bits up and I took my ecig with me as normal and a spare battery in my bag. We were out for around 45 minutes when walking back to the car chatting away, I heard a huge bang and saw what I thought was something flying towards me from the corner of my eye. My husband shouted from behind me "it's your bag", came running towards me and grabbed the now flaming bag from my arm, and threw it away from us while I patted out the flames from my arm and side. Pretty much in a state of shock for around 15 mins with people crowding around asking if I needed an ambulance but I assumed I was fine as I was in no pain and just shook up. However, the pain kicked in when I sat back in the car and then noticed my back and upper arm were blackened with soot and had nasty burns underneath it. Big burn holes in my t shirt at the back and under the arm where the flames had eaten through them. My phone and money and bank cards all melted. According to onlookers it shot out of my bag like a rocket leaving a ball of flames behind it. Needless to say, probably my own stupidity keeping it in my bag with other stuff but genuinely didn't know it could cause something like this. Always make sure we buy genuine products so thought we were as safe as we could be. Won't be taking a spare out again!

Can you summarize the given text in a few sentences?
<bot>: took spare ecig battery out in my handbag, exploded in my bag, burned me and melted everything in there.