5+3 slight spotting

Michelle

Well I’m pregnant with Babe #5 my youngest is 10 months I had spotting on and off till 8 weeks with him , but I only remember brown well this morning I went to pee and when I wiped ( partner and I did have sex) his ahem jiz come out but had some slight red blood streaks not a lot but was enough for me to freak out of course !! Have been toilet 2 times since and nothing there now . I have had a sore back for 3 days and a pain in right leg . Anyone else spot after sex ? Should I worry 😕