How serious should I take this

Received this email, and Im not gullible. I know about these type of scams.

However, what concerns me is they did in fact send the e-mail from my own email address to myself. I assume they hacked into my Microsoft account? While I can change passwords, it leaves me wondering if they could have hacked into any of my other socials (insta, snap, whatsapp, yt, discord etc)

Any recommendations? How serious should I take this ‘hacker’?

Thanks