Can't login to wp-admin

I’m kinda new to the wordpress thing. I uses mamp and set it all up so that it was running correctly and spent the last few days working on my site. Today, just before I finished, the site logged me out and won’t let me log back in. I can log into wordpress.org but not the admin panel.

I have sent my self password reminders but I never get the reset email. I have tried using the user name and password from my welcome email and it won’t work.

Can someone explain what happened? and how to fix it??