implantation bleeding?

Nicole
This may sound like a stupid question, but I am on the pill and have been for about 2 weeks now. After about 8-10 days of use of the pill I have unprotected sex but he pulled out, we did this twice. Now I feel like I am getting implantation bleeding (Note: I am on day 15 of my pills by now.) 
What do you think this is?
It's more like spotting to me, and it's very light, pink. It's thick like discharge. It's been happening for atleast 4-5 days now. 
Thank you for any comments :)
Also, I've been sick for over a week now with a bad cold going around, so I think it would be hard to see pregnancy symptoms. 
I know the best option is always to wait and test but I just wanted someone's opinion on all of this first.