TTC #1 with fibromyalgia

[BH040]

My fiance and I have been trying to conceive our first for the past 9 months.... I have been tracking my cycle and it flip flops between 27 and 28 days. May was a stressful month on my fiance for work and other things so we only tried a few times this month. the last time was just about a week before my period was due. I thought that it had come right on time, but it has been EXTREMELY light. There was only one day where it was even in the realm of normal for me. Usually the first two days are a little less than heavy and then its not an extremely light amount but its there. Well I am on day 5 if you count the first really light day whcih was barely anything or day 3 if you count the semi normal day... I have not been stressed out, and I haven't changed eating/exercise habits at all. I took a test and it was negative... I have been reading articles and posts on a million websites and some say that it is possible to ovulate more than once a month although unlikely, and that ovulating 14-16 days after the begining of your last period is just a generalization that it is not always that certain.... I guess what I am asking is if anyone thinks that this is cause to be careful of what I take until my next period is due? I have fibromyalgia so I usually take melatonin at night to help me sleep and it says do not take it if you are pregnant.... so i am not quite sure what I should do???