How to make yourself vomit? I've tried sticking a toothbrush down my throat, it won't work?

you might lose weight, but I guarantee you will not feel better! So it's not just a matter of health, it's a matter of reality, you will make things worse, when there is absolutely no need for it. Keep exercising, keep it enjoyable and eat a sensible diet that supports your system, so your brain and body can handle the exercise and make it work for you, it just takes time and being realistic not drastic.