Help to explain this to my mom?

If you are a young adult, having difficulty controlling your emotions is part of that developmental stage. It's a rollercoaster and there's no denying that. It sucks, but it's pretty normal. On the other hand, if you're into your 20s or older and having trouble controlling your emotions, there's probably room for you to learn some ways to rein that in. Some people are more prone to being really emotional, but that doesn't mean it can't be controlled. You may just need some support learning how to do that, maybe with a counsellor or someone else who knows about that kind of thing.

Well I believe we all have a certain amount of control over our emotions. Unless you've been die diagnosed with a severe mental illness I think what you're really saying is you don't want to try and control your emotions. Try telling your mom that.