Placebo pills

Chey
Ok so I'm on Junel Fe.
I was experiencing serious breakthrough bleeding for a good week and a half.
I'm on my last week of my first pack(month), which are the Placebo pills. 
I was under the impression that they are supposed to bring your period on? I'm no longer spotting, just a little light brown discharge. Should I be worried?
I really want to have sex, and I haven't been able to due to all this spotting. Should I just go for it or will having sex cause me to bleed ? 
I need answers 😩 thanks ladies.