Sir i've mistakenly clicked new preference option but did not update anything and my current preference list is showing as it was earlier and I have checked it after logging in and out also checked it next day and it was same as i did the first time, was my preference list deleted?
No, your preference list is not deleted. As you don't update the prefence. Only when you save the new preference list. Then it will be updated otherwise it will be the same. So you need not to be worry.
Good luck !