Could Light Spotting After Having Unprotected Sex Be Implantation Bleeding?

Hi I'm Amber. I'm supposed to start my monthly cycle Saturday February the 15th. But today at 11:30am I noticed when I went pee and wiped I had a very light pink blood on the toilet paper. I had sex on Wednesday the 29th of January and it's been two weeks yesterday since I had unprotected sex. Could this mean implantation bleeding ?