can i be pregnant if hpt came back negative

I have one tube from a previous ectopic i am 38 years old and have been trying for a little over a year i am 6 days late with my period i took the "answer early pregnancy test" and used for morning urine it came back negative.. I have all the symptoms of being pregnant is it possible that the hpt is wrong and I am or could I have skipped ovulation ( seeing as i only have one tube) i am NEVER late in fact when i stress i am early so this is very puzzling to me?? and i have alot of clear discharge i keep thinking i got my period and run to the bathroom and nothing???? thanks for any help..