I normally spot, have my period and spot on the last few days and a normal period can last up to 7 days. Are you outside of that? But since it is new for you, then why not have a pelvic exam and discussion with your doctor?
Normally, you can get an accurate pregnancy test 2.5 weeks after your last unprotected sex. Are you trying to conceive and that is why you started having unprotected sex?
Your post is confusing. Do you have reason to believe you're pregnant?
All this spotting, rather than a usual 5 day flow is concerning. Do you have a regular doctor?