Is my girlfriend pregnant?

My girlfriend and I decide to take our relationship to the next level and try to have sex. I first had intercourse with her on June 21. I used protection and did not orgasm. We stopped because the pain was to much. Now on Wednesday June 29 she noticed light spotting. she said it is more of a pink color than red. Does any one know what this might be? Its not her period because it ended the day before we decided to have sex. I am aware of Implantation bleeding. thats whats freaking me out