Trolly61
I sympathise entirely with your feelings - it is a 'generational' thing, and I understand your discomfprt.
What you need to appreciate is that your son has 'hidden' his personality up 'til now, probably in deference to your feelings, but now that everyone knows about his sexuality, he feels able to express it openly, albeit rather more 'openly' than you feel comfortable with!
Why not have a word with him, and point out that although you love him, and respect his rights to be whom he is, you have rights as well, as do your family, which are being affected by his current need to advertsie himself to the world at large.
Explain that you have no problem at all with his sexuality, any more than you would if he was a nudist, but maybe at home he would keep his clothes on, to save embarassment? By the same token, maybe he might like to save his more outre wardrobe and manners for his social time, and tone it down a bit for the family.
This is a perfectly reasonable request, and hopefully, now that the giddy euphoria has worn off, your son may see that society still requires certain behaviours from us all, and we act accordingly to fit in with our loved ones.
Hope he can see the wisdom of your view.
Good luck.