What Causes Delayed Periods And White Discharge On Withdrawal Of Birth Control Pills?

To start off I am 19 years old. I was taking birth control but I kept forgetting on some days so I decided to stop taking and wait a month to start taking birth control again. I have not took the birth control yet cuz I relized when I stopped taking the birth control I get this white gushy and smelly stuff on my under wear. On top of all this I have not got my period and I have not had sex what s going on?