Confused if I can be pregnant? Answers?

Hello , my name Is Coral . I have a question I was on the depo on July & I missed my depo shot on Oct. 5th. I only had 1 shot I was new at the depo . I missed my shot & I never got back on it since the depo didn't work for me . It's been a few months & my period comes on time . Now i gotten my period on January 31st & it ended on the 5th of this month . Now , I thought I was gonna get off my period on the 4th but I kept spotting till the 5th so I counted that day ..me & my boyfriend had intercourse on the 7th, 8th & 10th. I have a app that controls my ovulation & when I checked it says I was firtlized on the 8th-Today since I'm ovulating today . We didn't use protection & he said he did ejaculate . Now can I get pregnant for having unprotected sex 2-3 days before ovulation ? & im kinda confused on if I count the 5th as the day my period ended since I was only spotting ..it confuses me on if I was ovulating today or yesterday . I just need to ease my mind can I please get some answers ?