I can be so stupid

I had my son 6 months ago  I pprom'd at 25 weeks but didn't deliver till 35 weeks he dad is a total arse hole wasn't there when my son was fighting for his life he see's his son when I take him to him I've taken him today to see him and like a twat I've slept with him my period is due in 5 days there no chance I'll get pregnant is there? Xxx wishing you all a lovey and happy new year