I am in a really good mood. 

I just came out of AP Physics, a class I’ve been struggling with all year long. But today was different.

My teacher was writing a problem on the board with about 12 steps, and suddenly I had a breakthrough. I figured out a way to do it in 2 steps. I tapped my friend Brittany on the shoulder, asking for a confirmation that I was right. She encouraged me to share my theory with the class.

I raised my shaking hand in the air to be called on, and miraculously, when I tried to speak, the words came out how I meant them to. After double and triple-checking my theory, my teacher and the class determined that I was right!

I know I shouldn’t feel like I have to prove myself all the time, but I was starting to worry that people in the class thought I wasn’t very good at physics. I’m probably being paranoid, but here’s the deal: after I figured that out, the physics supergeniuses turned around to look at me and they smiled. I had impressed them, and it was an incredible feeling.

In fact, you know what it felt like? It was a 500 Days of Summer “You Make My Dreams” moment. I totally felt like Tom Hansen, ready to high-five anyone I met. If you don’t know what I’m talking about, watch this video.

Hall and Oates’ “You Make My Dreams”  is the perfect feel-good jam. But 500 Days of Summer’s  Joseph Gordon-Levitt takes it to the next level in this scene, starting with his adorable smile and ending with a full-blown dance sequence.

Even if you’ve had the worst day ever, I guarantee this will make you smile.

Have your own feel-good jam? Leave a comment, because I plan to put together a top 10 list soon!