There are definitely people who graduated from a non-business or engineering degree but works in the the bank. You shouldn't be nervous that you are from a non-conventional background since your background could also benefit the teams you work in, by bringing different skillsets or perspectives to the table. And anyway, finance/banking knowledge is really not that difficult to pick up at all. As long as you have the right attitude and put in the time and effort to close your knowledge gap, you will be fine. I wouldn't worry about it.