Does COBRA retroactively cover to day of original plan termination?

Hi everyone,

I quit my job middle of May. HR told me my health insurance would run till the end of May and then I would have to enroll in COBRA going forward.

Well, it’s not June 10 and COBRA still hasn’t mailed me anything and HR just keeps telling me to wait for something in the mail. I accidentally forgot I didn’t have health insurance and saw a doctor during this time. Does COBRA retroactively cover these appointments etc when I do enroll?

Thank you. I’m located in Ca if that matters