['I got to work yesterday and my coworkers threw me a party!', "That's awesome! Was it your birthday?", 'It was! I was so surprised and happy that they remembered it and threw me a party. It was very nice.']
Your friends care a lot of you and that's always a great feeling! I hope you had fun!
The other day when I got to work, my co-workers threw me a surprise birthday party. I was so surprised!