First I want to comment on two things. You call yourself a loser. Don't do that. You have identified your problems and seem to be willing to deal with them. That's what I would call a winning attitude. You are a winner. Give yourself that credit!
Second, your age is nothing. And I mean
NOTHING! Trust me on this one. Your brain is not even fully developed yet! It will be when you are around 25. The last "features" it develops is the ability for long term planning, like planning a life strategy, planning things years ahead. I have coworkers that are in their 40s and 50s and still have no game whatsoever, and are probably still virgins. They are complete losers. Never compare yourself to others, but if you still want to (because we all do that anyway) compare yourself to those who are worse than you. They will make you feel better about yourself.
Give yourself a few days to grief, and do whatever you feel like. And please overdo your griefing to comic levels. If you like comfort eating, make sure to fill your face completely as you go "I'm such a looooooooser!". Make sure to smudge out the food really nice in your face and on your clothes. Exaggerate everything. Feel sorry for yourself and do it properly.
When you can't take yourself seriously any longer, you go out and pick up some girls. Now you have a funny story to tell them as well.