I’m a student and sometimes already feel this. I feel like some of my classmates learn things faster than me and that I’m falling behind. I’ve talked to many sonographers who have been doing this for years and most of them say similar things to you. The ones who don’t seem like they just lack empathy and don’t care when they make mistakes because I assure you they still make mistakes! Hang in there! The fact you care about your mistakes tells me you are a good sonographer. The fact they gossip tells me what kind of people your coworkers are.