I'm so confused I need advice

My fincé and I have been TTC so the month of dec we had sex around my ovulation time and in January I was supposed to come on, on the 11yh never come on. I had a few symptoms of being pregnant. But I have gotten 3 negative test. With my son I didn't find out til I was 3 1/2 months. So 3 weeks later I saw brown discharge. The next it was a little heavier Then spotting but only when I wipe. It's now day 3 and it's back to only when I wipe and going away. My next period is not supposed to start til the 8th of February. Could you have late implantation bleeding? Also my periods are about 4 days now 28 day cycle and I have a light to medium flow. This is to light to me. I've been reading so much but nothing dead on. Please help!!