Created a new account on twitter. No link with any previous account, neither email, nor mobile number, dob, name or anything. But my friend followed in just 4 mins after I created. Was it just a coincidence?

If you didn't run that in a container or something, they probably got you through the usual Facebook, Instagram, etc. Besides that, I guess it could also be because of your browser account (Google/Firefox), or even fingerprint.

I'm far from being a pro in profiling, but there are many ways to know that a certain profile belongs to a certain person.

@Jilano i created from the same machine I use my old twitter account. But I opened the incognito window to create the new account

Does your friend use a bot?

@amitgupta While the incognito mode will clear cookies and history upon closure, it doesn't block any tracking.

You could always try again from a different computer/network/browser and see if the same thing happens again. (If you really want an anonymous account free from your friends ;)

@Jilano that account is for a tool. So I any how wanted to share. I was just wondering how twitter is smarter than me.

@Stuxnet hehe no chance