Congratulations! This just goes to show that, if you follow your passion, success is inevitable. Most people who graduate from college wind up in jobs where they sit in a cubicle all day long, doing work that has little or nothing to do with what they majored in for their degree, and wishing they had taken a chance long ago to follow the road not taken. You now have a small taste of what life down that road not taken can be like - do not forget it! It's the kind of inspiration that drove many successful people to great achievement despite naysayers and doubters, often requiring many years of hard work. Use The Force! Feel The Force!
That being said, you don't want to spend the rest of your life leaping off cliffs all of the time with a hastily-packed parachute. You want to maintain that passion over the long term, but, channel it toward some specific goals that are fairly simple to define in a handful of words ("Develop a credit card size Linux computer that will sell for $35." "A computer for the rest of us." "Put a personal computer on every desktop."). You always want to have a 30-second "elevator pitch" that you can recite without thinking about it because it will flow from your passion. You want to always be ready for when those once-in-a-lifetime opportunities arise when least expected.
You realized how you were forgetting key points you wanted to get across in your presentation, but, you saved the day in the give-and-take Q&A session. You want to excel at both parts of that experience, because if you flub the first part too often, you may never get to the Q&A part. Unless you're prevented otherwise, there is nothing wrong with having some notecards at hand with salient facts and figures, especially if the information is of a rapidly-changing nature. If you have them, you'll find that you often won't need them, but, if you don't have them, you'll wish you had prepared them. The preparation is the key, not what's on the cards - we remember a minority of what we read, but, a majority of what we write.
Politicians and newscasters use telepromters almost all of the time, but, the most successful don't just read from them, they riff on the words displayed. The papers you see on the desks of newscasters are thoroughly marked up by them within minutes of going on the air, even though the copy may have been printed out only minutes earlier than that. Sometimes, the copy on the teleprompter isn't quite up-to-date, and they need to be able to improvise - having those last-minute notes in hand gets them through it.
It was a very good idea to practice your presentation to friends - many people never do that and don't realize until it's too late that they're not getting their message across (and some never get the hint because they're so wrapped up in their own head/ego). Practice really does make perfect, and overnight successes are always the result of years of preparation. Passion is the dessert topping that brings it all together, so, always include that ingredient in your recipe - it's what separates the good from the great.
Carpe Diem! Sieze the Day!