Although I didn't register, an account already existet for my email.

[vcom]

When I began to create an account and entered my email, it turned out that my email has already been used to create an account by someone else. Actually, some time ago I got an email from spotify, but I thought it is some advertisement. What can I do, to be sure that nobody else has access to my account? I changed the password, but I don't feel secure.