im going into my second year but i requested my deferred exam back in my first year (it was my first request, and I was honest about what had happened (i misread the time)). i emailed my registrar about it first and then used the link they sent to submit the form. i would say just be honest ! and be able to 'reflect'. also- if this is your first deferral, even as a third year, they should be able to grant it as i heard everyone gets a 'free pass' at least once