The only way an adult can acquire HIV is through unprotected anal or vaginal sex, or the sharing of IV (hollow-hypodermic type) needles with an HIV+ person.
HIV is not the horrible nightmare virus portrayed during the 90s. It is actually much harder to acquire than most people would think, and is actually much more rare than most would realize. Less than 1% of the population is currently infected with HIV.
Further, HIV is extremely fragile and is soon inactive after leaving the body. Bottomline, you would not have acquired HIV from stepping on "period" blood, or by tracking it in to your living spaces. Your baby was not at risk of acquiring HIV from this dried "blood" stain.
No risk...as HIV virus has very short live out side human body...even if u read online u had no risk ...the risk is sharing needle or unprotected sex ...