Could I be pregnant???

My hubby and I have been ttc since august when I got my IUD out. I have had super regular, normal flow for me periods since then. We tracked Ovu this month, had sex every day of fertile window, etc. I feel different about this month. Got what I thought was my period 1-2 days late (depending which app I looked at) this cycle, but it never got heavy, it stayed super light, pink or rusty brown in color, and would even stop for hours at a time before spotting again. This lasted off and on for four days (my period is normally 5-6 days). I have been super bloated, nauseous, peeing every hour on the hour, crazy mood swings like I’ve never experience, super tired out of no where. I just generally feel off. I got a BFN on a cheapie strip test on day 3 of my weird spotting adventure, and have been too afraid to test again in fear of letting myself down. This would be almost week 6 if I am pregnant, should I try testing again to see? Or is there like no way I could be pregnant? Anyone have similar experiences??? I’m so confused right now because this has never ever happened to me.