Could anyone help me?!

So I’ve started with medication since thursday. I take Rubió (better known as Ritalin or methylphenidate/MPH/MPD) 5mg twice a day (at 8.30 am and at 12.30 pm) always after my meal. But since thursday I feel really sick. My stomach hurts (not my belly, but my tummy) and my intestine also, it feels like it’s kind of restless. I also feel the whole time like I have to vomit. I only eat my breakfast and lunch and dinner, and take my medication after my meals. I have a very bad headache and I’m scared that I can pass out every minute. Does anybody here have experience with Rubió, Ritalin or another methylphenidate (Hydrochloride)/MPH/MPD like Concerta, Medikinet. If you comment, please say what you use, or used, and if you have or had a depression and suicidal thoughts when you used it and if that worked together (Ritalin and depression/suicidal thoughts).