Spotting after sex 2 days after period??

My period started the 15th, it was normal the first day and the 2nd day only i didn't have cramps anymore. The last 3 days I had dark brown/red spotting and could only use a pantiliner. Last night my bf and I had sex and I noticed I had some red spotting but it stopped after that one time. I felt like I was going to get cramps at one point but never did. It is hard for me to tell because I also get a burning/achey sensation in my lower back/stomach that goes down my legs from lupus. Any suggestions? I am going to my primary tomorrow so I will let him know as well. Thanks. -Brittanee

P.S. I took a pregnancy test the first day of spotting during my period to be sure and it was negative; i also missed two days of meds yesterday and the day before.. not sure if it has anything to do with it or not but thought i would mention it.

could be a hormonal imbalance - i have had those before with very similar issues . . . my gynecologist had me do 2 months worth of basal body temps (take your temp every morning before you get out of bed) and chart the temps . . . turns out i wasn't ovulating (most likely due to fatigue & stress) . . . a couple months of hormone therapy and rest did the trick for me

definitely take it up with your primary, though . . . there could be other things going on

Thanks for the reply. I am still having symptoms with my UCTD/SLE. They are 50% better but my dr is considering low dose pred. if they aren't any better in 3 months. I am however having a dilemma with the period thing, I have a 2 year old son who is to be 3 in june and my boyfriend and I want another baby. Are lupies usually fertile? I really wanted to be off meds when pregnant but I have no idea how long it will take or how long ill be on them or even if ill ever really reach a remission and stay there. Any suggestions? I am going to be 22 nov 7th. I dont wanna go through menopause yet ****! Thanks again though. Hope you are well. :) -Brittanee