How did you stop being a hypochondriac ?

Being a hypochondriac is taking a toll on my mental health. I have a minor cough and think it’s pneumonia, my ear hurts for 2 seconds and I’m sure I have an ear infection. Just last night I finished my shift in the NICU and was constantly exposed to a baby with MRSA and now I’m convinced I’m gonna develop a lesion on my piercing. It’s debilitating really. How do I stop?