When to start taking birth control

Ol

Hi, last week I went to the doctors and got the contraceptive pill but my doctor told me to wait until i first noticed spotting of my period to take the pill as it wasn‘t for a week. I have just started spotting but it’s 9:30pm and I was going to wait till the morning to start taking the pill however this weekend I would ideally like to not be on my period. Will taking the pill actually stop my period or just make it lighter?