Have you been eating a McD diet before pregnancy? I am not currently pregnant, but i did just complete a McD'ing pregnancy. My son is 7.5 months old
I did have some nausea in the first trimester and major food aversions. I am generally a simple eater (plain raw veggies, plain potatoes etc.), but in my first trimester, i cooked for myself nearly every day! My rule was that i had to try very hard to find something whole foods, low fat, plant based to eat, even if it wasn't my "normal" foods.
I ate a lot of brown rice pasta with homemade pasta sauce. i went through phases of eating a cold rice salad (aloha salad....pineapple, cucumber, red pepper, onion, rice vinegar etc.), i ate quite a bit of fruit, and i liked puffed rice cereal sometimes. I liked fruit leathers for a while. Corn tortillas fit the bill some days. There were two days where i wanted tabasco sauce on everything (?!) and now i can't look at the stuff. haha. It was crazy.
Basically, i would ask yourself what would be decent and just try hard to make it. For subway for example, how about get some good quality oil free bread (ezekiel if you have it) and put a bunch of veggies and pickles on it if that's how you like it.
Hope that helps....
Stick with it! You're giving your baby and yourself the very best nutrients you can. Give yourself the time and space to cater to your "wants" every day in terms of food.