I agree with Kimberlee_20, about the possibilities, and the fact that you've only been on them 3 weeks, and missing so many...you could be pregnant. BUT just so you know as a side note, your hair color may not have anything to do with this. I've dyed my hair a brown and it turned out black, but after a few washes and a little time it lightened to the color it was supposed to be. Most of the dyes, no matter the brand, I've used come out darker to begin with and then lighten as time goes and the more times I've washed my hair.
You've only taken the B/C for 3 weeks, and you've missed some pills? Most B/C's you have to take at least for a month before they even become effective, and missing some pills increases that risk of pregnancy. You can test two weeks after the last time you had sex and if you're pregnant you should get a positive HPT, or wait until your period is due to test (make sure you test with first morning urine). Also, the pull out method is not a form of B/C, you should always use a condom or another form of B/C on top of your pills incase one fails you have a backup, and condoms protect against std's. Good luck!