Your little guy is going through a completely normal stage that incorporates imagination and wishful thinking. He'll gradually comprehend the difference between real and not real over the next 3-4 years. And, as Patricia G. mentions, kids haven't yet got time and event sequencing figured out. So the best way to handle it is often a non-committal comment, without too much emotion attached to it. He will gradually figure it all out, and learn to more accurately follow the examples of the adults in his life. And his peers (sigh…).
I recall as a first-grader, desperate to have an interesting story for Show and Tell, I made up a whopper about jumping out of a plane with a parachute. I got stood in the corner as an example to the rest of the class, and that hurt. But not as badly as never having anything interesting to show and tell the class about.
And it sounds like your son may also beginning to explore the edges of social convention – what happens when he reports some startling news to an adult (or another child)? How do they react? How consistent are the rules; do they apply to everybody?
If this is so, then he's also going to be acutely aware of when he hears his parents telling some untruth, or partial truth, or kind fib. So be prepared to be challenged, both by his calling you on it, and by hearing him learning to do the same things as he grows up. Studies show that adults lie shockingly often! Here's a fascinating article – the latest understandings about why kids lie: http://nymag.com/news/features/43893/. Well worth reading.
And you can also google 'toddlers lying' for all kinds of information about how to handle it. My best to you!
ADDED: Oh, and incidentally, when we require a child to say he's sorry when he's not, or when he doesn't even know for sure that he did something wrong, we are teaching that child to lie as social convention. I think it's far better for a parent to explain why a behavior is wrong, and give the child time to ponder it and reach his own conclusions. As his capacity for empathy and compassion grow, he WILL realize he's sorry when he hurts someone or breaks something.
I have the most precious letter that my grandson dictated to his mom, a full two weeks after breaking a toy of mine that I let him play with, telling me he was sorry. He was not prompted at any time to apologize. When he was ready, he did, and it was loving and authentic.