Is it crazy to think there is still a chance?

I have never posted before, but I'm driving myself nuts. My husband and I have been trying for 18 months now with no luck. This month things felt different. My boobs were intensly sensitive from like 3 dpo until 11 dpo. On 10dpo I had some spotting not enough to fill a pad and then a couple hours of spotting on Saturday stopped and then a couple hours on Sunday. No flow like AF or anything and it was a lighter color like it was mixed with cm. I kept thinking and still keep thinking AF has started because I feel wet to go to the bathroom and there is nothing. Now it is Wednesday and I got a bfn this morning. Was it just a really messed up AF this month or is there still some hope. My lower back has been really sore since the bleeding which has never happened before, I can barely stay awake all day at work, and I am barely eating because I am so nauseous. Any help please.