I always knew I was pregnant from the extreme exhaustion I felt. When I almost fell asleep driving home with ds in the car on a warm day, I stopped at the store for a test.
I cried easily and my anxiety was worse, especially with dd's pregnancy after my m/c, when I would sit and worry I would find myself mindlessly pulling out strands of hair. I was very happy when she was finally born.
My sense of smell was also out of control, but each pregnancy was different. With ds, I couldn't have coffee in the house at all, I made dh stop for coffee on the way to work every morning. With dd, I had no issue with coffee (I think i was too darn tired from running around after ds and needed my cup a day), but I almost lost it in Costco when a roasted chicken was in our cart, dh had to take it away fast. Both of those smells will still upset my stomach when I am feeling hormonal.
With ds, I bought a case of mandarin oranges at Costco and ate them for lunch every day for two weeks, my coworkers thought I was gross. With dd, I practically survived off of Carl's Jr. I had ds and was babysitting a toddler and never ate enough during the day and felt awful and desperate for food by the evening, so dh would pick it up for me multiple times a week. I'm surprised dd wasn't born a zucchini fry.