A lot of thoughts on how to approach this come to mind, some in fragments, some more complete than others, but none of them are about running away. After taking some time to clear your head and get some food in you, the realization that they are just curious finally gets through. Taking a deep breath, you walk towards the podium. Halfway there, they quiet down and get ready to hear what you have to say.
"Uh, hi." You wave and give a smile. Some of the ponies are looking at your hand rather than you, so you make a peace sign. "I come in peace." Remembering this is an old movie thing that aliens did, the hand gesture probably doesn't translate as well. Feeling awkward, you decide to go all out. "Hello everyone, my name is Anonymous, or Anon for short. I have no formal experience in public speaking, and because this was on such short notice, I don't have a speech prepared. I'm a pretty weird looking creature, formally known as a 'human'. I have absolutely no idea how I arrived here, and my memories are still somewhat hazy. I know my stature may appear a little intimidating, but I can assure you that I'm as friendly as they come. Sure, I may have been a little scared when I first arrived," you raise your bandaged arm and point to it, "but now that I've had the chance to meet just a few of you wonderful ponies, I think that we're going to get along swimmingly as friends. Yes, I am an alien, and I just want to get back home. It may take a little while to get used to each other's customs, but I hope that over the course of my stay here that we may all grow to love and understand one another as equals. That said, I believe this will go smoothest if I get straight to answering questions… and before anybody asks, I do not have super strength, can't spit acid, and cannot cast spells. Those rumors are false."
You hope that went well. After a short while, they begin to talk amongst themselves, then they raise their voices so you can hear. You can't hear every single one, they come flooding in without a chance to answer.
"How do you balance on two hooves?"
"Can I see your spaceship?"
"What if you can't get back to your planet?"
"Well, I think he bleeds acid."
"His clothes look weird."
"Did you shave off your coat on purpose?"
"Is it true that those tentacles on the end of your hoof elongate and you use them to eat the brains of ponies?"
"Where's his cutie mark?"
"I still can't get over how he stands."
"Are other humans coming?"
"Oh, do a trick! Something amazing!"
"Where is he going to stay?"
"Are you part machine?"
"What if he's nothing but machine?!"
"Well, if you aren't strong, what are you?"
"I say we send him to Canterlot."
"Did the Princess say anything?"
"Seriously, look at how he's standing!"