A leak of cerebral spinal fluid would likely be from the nose or the ears.
A migraine will often cause abdominal discomfort and nausea, so that may be why you vomit.
There are a number of medications used for migraine, but they can be expensive and may not be advised for children.
Supplementing magnesium can help headaches and migraines.
See the article "The Importance of Magnesium to Human Nutrition," by Michael B. Schachter M.D.
If the url is missing, you can do an internet search for the title.
Wishing you the best,
Please take my advice seriously. You are clearly very intelligent and informed but you are 12 years old. I am relieved that your email address was hidden as you tried to post it (as all email addresses are). You have to be very careful about information you share with others on an open forum, and be aware that this is really for the most part an adult forum. I really am not trying to talk down to you but I am concerned. There are bad people on the internet, who may wish to talk to someone your age for harmful reasons. This is in no way a comment on the person who replied to you, she is clearly genuinely being helpful. But it is best I think not to tell forum members your age as you are so young, and even better to perhaps visit sites and forums more suited to kids your age. If anyone leaves you messages or notes on your profile page, please talk to your parents before replying. They may be fine but people online are not always who they say they are. Regarding your health, I wish you well and hope you feel comfortable to talk to your family and/or doctor about your problems. I've posted this because I am worried for you. I hope you understand my message.