>>76144251/ You aren't a loser until you give up. Currently you aren't a loser.
2/ Remember the you at 20 yo. Wouldn't you say this 20yo dude was a child? Bet what, at 25yo you'll still be a child, you have so much things to understand about the world. And guess what, you'll feel the same when you'll reach 35 about you at 30! I presume that's why your mother laughed.
3/ It's hard for most parents to accept that their daughter's boyfriend. They'll eventually accept you as you show proofs of your ability to make her happy, years after years. Be nice to them and focus on your and your girlfriend's happiness, it will be fine sooner or later.
4/ You are going to find work in the future, be open, you'll have to do stuff you weren't prepared for, very often. And as long as someone trust you on a job as a beginner, he'll be okay with you beginning bad and becoming good with time and hard work.