Compromised Email?

So a couple weeks ago, I had an email sent to myself and contacts in my address book (here on Yahoo, of course) under my name but from a different email. It was some website advertising a weight loss solution. I changed my password and I never got another email. Today I just got another email that was sent to my contacts as well under my name but from another email address, and it wasn't the same one as before. I didn't look at the message content yet, but the email was from an address that had to do with a hotel called the "Bookington Hotel" or something like that in England. I'm really scared that my email might be compromised and it's very stressful because the email is being sent to my high school teachers that have in my address book, even my high school's assistant principal which worries me more than the other teachers. I don't want them to continue getting this spam from me. What should I do?