Can having a severe UTI affect the results of a home pregnancy test?

[mallorie]

My periods have never been regular and vary from 4 weeks to 6 weeks in between. I went to the emergency room on the 29th of December thinking that i was possibly having a tubal pregnancy, as I had very bad pains in my right ovary and my lower back. They took a urine sample at the ER and told me that I was not pregnant but had the worst UTI they have ever seen. I took the Macrobid they prescribed me for my UTI but it still seems to be lingering around. I thought I started my period a few days ago after using the bathroom and seeing pink discharge on the toilet paper. I put a tampon in; no blood. The pink discharge has happened once since then and as I was urinating a little bit of red blood came out. My breasts aren't sore, but I've been nauseas (have thrown up once), am incredibly tired all the time and have been getting headaches (which is very rare for me). I've taken two home pregnancy tests and they've both come back negative. I was wondering if anyone had any information on whether or not a severe UTI could cause a 'false' pregnancy test? Any information you could give me would be very helpful! Thanks in advance!