Implantation bleeding? Baby #2?

Hi ladies, I got a question I would like you guys to help me with. I recently had a baby girl 2 months ago on March 9. Me and her father were doing good we had been dating for 2 years but we recently broke up due to problems but we've been trying to work things out. We use to live together but since the break up he went to live with his mom and I went over on May 6 and slept over so we had sex. I had gotten the paragard iud 2 weeks before so we didn't use a condom. Now I noticed today I had some light blood when I used the bathroom and I'm worried it could possibly be implantation bleeding? I haven't bleed previously to this. I'm very scared because I feel this is too early for another baby, plus we're having problems. And I'm only 18 and he's 19. Has anyone had implantation bleeding this early? I had been told implantation bleeding could happen anywhere from 3-12 days after sex.