Pregnancy & ESRD: A Patient's Story - Conception After Period & Hemodialysis

Question
I'm 24, I have one living Child and one deceased. My living child was born before ESRD and was born at 28 weeks. My deceased child was a twin(the first twin passed at 15 weeks) during peritoneal dialysis and passed at 27 weeks. The fact that I conceived twins baffled everyone. Because of irregular periods including not having one for months at a time, I didn't find out I was pregnant until 15 weeks. The fact that they lived that long without a change in dialysis prescription had everyone amazed.

November 15, is the first day of my last menstrual period.

I had unprotected sex with my boyfriend 3 times. Once each day on November 11th, 12th and 14th. I have not had sex since. I got my period on the 15th. Today is the 18th of December and I still don't have my period. I have in the past experienced irregular periods but it has been a couple years since that. I have been on Hemodialysis for 2 years. The 2 years preceeding that I was on peritoneal dialysis. I found out that PD really didn't work as well for me so I switched. Any irregular periods have stopped since then. After switching to hemo, i didn't need blood pressure meds anymore etc and I know medication as well as the 20 pounds of fluid weight I lost after switching can be a factor for irregular periods.

Is there any chance I could be pregnant? From everything I've read, it seems that the sex wouldn't have been during my fertile days but if I have learned anything its that when it comes to my body, all bets are off. I can't take a home pregnancy test because I don't make urine anymore. Thank you in advance for your insight.  

Answer
If you had your period on November 15, and have not had sex since that time, then you cannot be pregnant. It does not matter if you had sex prior to November 15. If your last period started on November 15, then you would have ovulated around November 28 and could only have conceived if you had sex on November 27,28,29, or 30. The best time for a pregnancy test is seven days after missing a period. YOu were due for your next period on December 12. The best time to take a pregnancy test would be on December 19. If it is still negative, you are definitely not pregnant.