If you sat next to someone who had the Stomach Flu, can you catch it?

I'm a huge germaphobe with a fear of vomiting, and on Monday, my friend missed most of her classes because she had the stomach flu (she threw up). I sat next to her for about fifty minutes during a school assembly. She didn't cough on me, although she definitely breathed on me. It's been roughly forty eight hours since she got sick, and over forty eight hours since I sat next to her. I only talked to her for a moment today, long enough to find out she got sick, after which I promptly went to wash my hands. I felt a little sick yesterday and this morning, but now I feel mostly fine (although I have a headache because I started hyperventilating a little, and my stomach hurts a little. But it is lunchtime and I haven't eaten yet, so that could be the cause).

So, explanation aside, if I sat next to her for 50 minutes, but she didn't vomit on me or cough on me, and we didn't share utensils or food or anything, and I haven't thrown up yet, am I ok? Is there still a high chance that I will get sick? My school nurse thinks I should be fine, but she's used to reassuring me that I won't get sick. I can be forgetful when it comes to washing my hand and putting them near my face, but I try to remember whenever I can.

Thanks for putting up with the paranoia of a Germaphobe XP