Took off today and nothing sounded or felt right. I couldn’t put my finger on it so at 1000’ I turned around and landed. Didn’t notice anything until I read a text from a neighbor that my cargo door was open when I took off. And it still was. Not my proudest moment. No damage to door or hinge and nothing fell out. I’ve wondered if that door would tear off the plane if it came open in flight. Not today. I have a new placard now!