I feel so alone

What you are encountering is part and parcel of culture shock - something every human who moves to a new and unknown environment feels to a certain extend. It is caused by how our human psyche reacts to uncertainty and it's inevitable cousin, fear (of the unknown).
There will be ups and downs and mood swings for a while (sometimes months) and you are well-advised, even if that might feel difficult or even impossible, to focus on the positive aspects of yourself and the new envronment.
Also keep in mind that your current mood is just that: A temporary feeling. It does not reflect on the long-term situation around or within you, which you can only evaluate when the shock is over and your emotional shape stabilizes.
I can also assure you that the people around you don't judge  or "unvalue" you (and neither should you judge them for what they are). If you have the impression they do, ask them about it - open and honest conversation is often a first step to understanding and healing.
But if you fall into a depression or feel suicidal, seek professional help. Do not flee into a perceivedly friendlier world (e.g. a mental ghetto, or back home): I have seen more than a few people fail miserably there, too, because your problems travel with you unless you approach and solve them first.
Good luck and enjoy the ride!