wear something with sleeves.
Your wedding day is just a day. You can do it however you like. Hell, you can cancel everything and get married in a reg office with 2 witnesses if that's what you want!
The wedding is not important. What is important is that you are getting married.
If you are stressed and worried about the day - change the day. It's only a ceremony. You have it however you want it.
ok, if it's coming up this saturday obviously that's different, but if it's months or a year away you have so much time. But either way - you are in charge of it. If parts of it are making you unhappy - see what you can tweak.
If, otoh, what you have concerns about is getting and being married, then the focus on hairy arms or pale skin may be masking what you're really worried about. It's normal to be nervous.
Weddings don't have to be perfect. They're supposed to be fun and happy.
You need to remind yourself that you are in control here. That you and your fiance are the ones who are making the choices. That it is never too late to change your minds about any bits of it - ok there may be cost implications, but it's not against the law to change your minds! And it's ok to have the day the way you want it.
It's one day. One party. It's supposed to be fun. If it's not fun then you need to look at why and change it.