Two questions about facebook?

[hello!]

Hi, I'm new to this whole social media trend so I really don't know what "rules" apply.
I got a Facebook somewhere around september. Other things, not so much, I don't feel like it's necessary. Instagram, snapchat, etc, no thanks!
But I basically have 2 questions about FB.

1. Is it slightly "weird" to have 55 friends? I really don't know people, and I simply am not the most social person in the world. I'm willing to admit this. The problem also is I recently moved, so no "bonds" were ever made with people from this place I live in. In my school, I only know people from my own class. I have no friends outside of that (well, a few exceptions, there are 2 or 3 people I talk to). And it's a pretty big school too.
So is it slightly "weird" to have 55 friends? The people who are dicks on YA! Answers can also go ahead and answer (not saying all of you are!), but go ahead, I frankly don't care if somebody wants to call me a "weirdo" or "creep" or something in that style. I have enough confidence to not be affected by online trolls

2. Birthday congratulations. 2 twins in my class today had birthday (2 guys I would say I'm pretty close with, we joke around and talk a lot and all that...) today. I congratulated both of them.
Is the thing now to congratulate them online too? I mean, I've already congratulated, but I see they get a lot of em online? I even saw a guy from my class congratulate one of them even though he congratulated in school too. What "rules" apply here?

I'm very greatful for answers!