Emotional rollercoaster - tested negative twice

I started getting really nauseous to the smell of my body lotions and fragrances starting at 8 DPO so I automatically assumed I was pregnant because of that since I have been wearing fragrances for years without issues.

So I decided to take a pregnancy test at 11 DPO, but it was negative.

Then, my period started at 14 DPO . It was light and it was brown in color on day one, which is usually how it looks the first day of my period so I was so disappointed and devastated. But day 2 of my period was even lighter and pink and color, which never happens. My period is always heavy by the 2nd day and bright red. Then day three it was also super light and pink and my breasts & nipples started getting sore, so I thought I must be pregnant. Then today it was super light and pink again and just spotting. So far I have been very light or spotting for 4 days total but my periods are always heavy. So I decided to test again today, which is 4 days after I expected my period and 18 DPO. I still tested negative today. I even squinted looking for the faint 2nd line, but it wasn’t there.

But I just read that I should have tested using the first urine of the day. But I did not do that. Both times that I tested, I used the second urine of the day which was an hour after the first one.

Is it possible that I actually am pregnant but testing negative?

This up & down of emotions has been overwhelming.