Unusual bleeding/spotting

[tash1978]

Im hoping someone would be able to help me due to being in the same situation. My periods are always bang on time and for 4 days. Last month a week before my expected period i wiped down below and it was a very light faint pink colour. By the next day there was a little more and only required 1 pad just so i dont stain my knickers. By the 3rd day it went back to light pink staining and was gone by the evening. My expected period date never happened. This month again a week before my period light pink staining the first day, 2nd day brown staining and then nothing. Expected period again didnt happen. 4 pregnancy tests and they are all negative. Has anyone else experienced the same and then found out later that they were pregnant. Im usually on a 25-26 day cycle. Im now on a 17-18 day cycle if thats even classed as a period. I am trying to conceive.