Re: Do other girls do this?
You’re not even sure if he knows about you?? Or even knows that he’s now “committed” to someone??? 
As others have rightly pointed out, 5 years is a long time. Anything can happen. People change. If I were you, I would put this “baat pakki” out of my mind, and just concentrate on studies and building a career. Don’t obsess over someone that is intangible to you. When the “5 years” is up, worry about it then.
Re: Do other girls do this?
Bless you, 18 is a good age indeed , you just live in another world that aint full of humans !
Just listen to your mom. Focus on your studies and try to get over this whole baat pakki thing. Talk to a few friends in real life if you must share , just to get the excitement out of your system.
Re: Do other girls do this?
Getting married early isn't really an option and we are engaged but only my family and his family know about it. They plan on telling everyone else when the time for marriage actually comes.
I know you don't need a year to learn desi cooking, but everything else too like bathroom cleaning, sewing, etc
I know my mom is right, but I'm not wrong either. Even when focusing on school, hobbies, etc there are still times of the day when I make time to only think about marriage and him :(
You don't need a year to learn how to clean a bathroom or sew either. Since you seem to like him so much, why don't you use the remainder of your day to learn these things so you can speed up the process a bit?
Listen, trust me...this engagement means nothing right now. He's young, you're young. 5 years later, if both of you are even interested in each other you'll get married. This is for your own good that we're saying these things. Just forget about him for the time being.
Re: Do other girls do this?
So you're engaged but not sure whether the guy knows about this whole thing? Yeh kaisi mangni hai?
If you really like him maybe you should just talk to him. Stalking him and wasting your time is not going to get you anywhere.