Funny, the first time I was pregnant, what went first was my smell! I had purchased for myself a new perfume but did not actually use it until a month later -- and in between, I conceived and was already 3-4 weeks along without knowing it. Then, one day, I opened the bottle only to find that it smelled like a skunk to me. I was so upset, and planned on taking it back to the store with an earful for the saleslady for selling me a "rancid, old perfume." Thankfully (for the saleslady! LOL), I never had time to do that, because a week later I noticed that I was both late and that both perfume and tuna smelled like skunk to me (I noticed while eating my lunch at work). I tested myself and I was pregnant.
This time, I was too busy with my son to pick up on early signs, I suppose...but I just remember that one day I was so exhausted, I came home from work and slept from the moment I got home at 6PM until the next morning, in my work clothes and everything. Two days later I made myself eggs for breakfast and they smelled like...you guessed it! That skunk smell prompted me to run to the drug store and sure enough I was pregnant with number two.
I still have that perfume...funny, all throughout my pregnancy I could not smell that fragrance in particular. Even after I delivered, for months it still smelled like skunk to me. When it finally started to smell like how I recalled it smelling in the department store, I still hesitated on wearing it -- it was weird, it was like I psychologically associated it with a bad experience or something. I just could not bring myself to wear it anymore.