I Gave My Boss a Fake Birthday Card

So, I'm this new kid at my first job out of college, and it's been going pretty well. The boss, let's call her Sarah, is friendly enough, always in the office with all these fancy plants around her desk. She has this huge glass vase full of what looks like random office trinkets and cards, she gets so many birthday gifts from clients or other bosses. One day, a co-worker whispers to me that next Monday is Sarah's actual birthday. The whispering got me thinking about how I haven't really put much effort into making friends here yet. Most of the team is busy with projects; nobody seems too chummy. So when the idea popped up again in my head this morning, I thought maybe if I was the only one who remembered and brought her a card, she'd notice me more. I headed to the nearest convenience store during lunch break, thinking hard about what kind of card would stand out from all the fancy ones. After browsing through dozens (okay, it felt like hundreds), I found this quirky little card with a funny cartoon cat on the front saying 'Happy Birthday! Be Pawsitively Awful Today.' Inside was an adorable kitty and some jokes. I put it in my bag and rushed back to work, feeling good about doing something sweet and unique. When Monday came around, I slipped it onto her desk early morning before anyone else showed up. But then... the wheels started turning inside my head. Was I being too obvious with this cute cat card? Maybe she wouldn't appreciate the humor or think it was unprofessional. What if everyone else thought I was trying way too hard? So now, days later, I'm still unsure about what happened next. On Sarah's actual birthday afternoon, someone from HR came in carrying a big banner for her and all these small trinkets, another card for every person here to sign their wishes. I didn't see any reaction or mention of the cat card at all. I've since noticed that the funny card hasn't been taken out of its place on Sarah's desk, sitting right next to a bunch of other cards and gifts. Is it even noticeable anymore? It's been bugging me ever since. Maybe I should have just gone with one of those boring, formal birthday wishes like everyone else does. But then again, where's the fun in that?