Is It Dangerous To Take Energy Drinks While On Vyvanse?

Hello, I'm a 22 year old female and I'm prescribed to 50mgs of Vyvanse a day. Today after I took my medication I had 2 energy drinks while at work. After I got home I started to feel really sick to my stomach all of a sudden and vomited. I didn't eat much today because I worked all day, and my medication makes me not hungry for the first couple of hours. Also, I work outside and it was over 100 degrees and I was sweating a lot. I usually drink a lot of water, most of the time with cucumbers in it, but today I know I've only one bottle, around 12-14 ounces. Also, I don't normally drink energy drinks, either. It's been about 30 minutes since I vomitted and I don't feel sick anymore, however I need to know a few things:

1.) is it dangerous to consume energy drinks while taking Vyvanse? Is it a serious health risk?
2.) was I dehydrated from lack of water, the extreme heat, energy drinks, and Vyvanse combined? And got sick from all of these said things? Why did this happen?
3.) What is happening inside of my body?

Please help me figure this out so I can prevent this from happening again.Thanks
-Rachel