When someone compliments me <3 My crush called me pretty once and I haven't forgotten and tbh whenever I feel more self-conscious than usual, I just kinda think to myself, "He called me pretty." and it legit just boosts my self esteem and my mood.
Also, when you're just chillin with your bestie and you're laughing so hard together that your stomach hurts and there's tears running from your eyes and you can hardly even breath and your mouth hurts from smiling so much afterwards but you have that beautiful feeling of happiness.