Launch day problems are rarely dramatic. They're a typo in an email address, a contact form nobody tested, a phone layout nobody looked at.
Hand your phone to someone who has never seen the site and ask them to find your prices, then contact you. Say nothing while they do it. Watching that once is worth a week of your own opinions.
Connect Google Search Console, put the link in every profile you own, and check your analytics once — not five times a day. Then leave it alone long enough to learn something.
On Volnyn hosting and SSL are already handled, so publishing is the whole launch. Start free at volnyn.com.