I'm not really sure whats going on

sorry this is going to be kinda long and detailed. So I had a bit of cramps about 5-6 dpo, a few days after that I had a ton of white cm for about 8-10 days and I was supposed to get my period on the 4th of June but it didn't come till the 6th. I have NEVER been late once and my period typically starts out at a medium flow but it started out pink. It only lasted about 4 days. I thought I should probably test, I got a BFN, a week after I tested and still got a negative. It has now been 5 weeks and I think I got a very light line but you can hardly see it. I'm just really confused about this whole thing and what's weird is I have been getting nauseous, some smells of food make me sick, my nipples are tender (also around them), frequent urinating, a little bit of bloating, just a few headaches here and there, and I have been feeling very tired even if I get a full 8 hours of sleep. Is it possible for your body to produce very low amounts of hcg??