Someone help? I need advice

What does this mean? Ive been taking Vitex Womens Health for a bit now to help concieve but from Nov. 1-23 I had a on the mid/lighter side of a period. WITH NO CRAMPS/OR ANYTHING. Then stopped, started up again Dec. 3-7 with no symptoms of a period and stopped. Then on Dec.19-21 I had a very light "cycle"-again. I tested on Dec. 28 and it came out a negative. Should I be waiting longer to test? I'm ttc and clueless. #Babydust