Missed period and a negative pregnancy test?

Hey guys ok so we are ttc and last month my periods were all wacky! I was on it for 4 days then off for 2 then back on for 6 and I was suposed to hey my period this week on Monday but I didn't I took a pregnancy test today and it was negative but I have so many symthoms I'm sick to my tummy and I have sore breasts and and I've been so moody and sleeping a lot like with my first child but I got a negative I'm so confused :/