+1 on all of the advice the others have given - The advice for a new seat regardless of price is a good one. Take it from someone who learned the hard way - you may not have any pain right now with really short rides but when you get to riding long enough that you do - it can become a show-stopper.

Eventually you will want some kind of padding for riding longer distances, (there are lots of choices here - liners that can go under anything, lycra and baggy shorts), but that certainly isn't something you need right away. You will have time to develop your own preferences

Congratulations on your new bike - and welcome to TE! No need to be embarrassed about your distance - those milestones are sweet when they come