First time pregnancy food freak out!

Victoria • I`m a 34 year old married woman! I`ve been with my hubby for 10 years and we have a beautiful 5 year old little girl and a 2 year old little girl! We’re TTC #3.
I'm having a nervous breakdown right now about going shopping for food. I generally eat really clean foods, and I was going to switch from coffee to herbal tea. No big deal! I'm healthy! I haven't gotten to speak to the doctor or gotten any information short of what I've researched until I'm 8 weeks (which is in 4 weeks!) so basically after researching I'm of the mind that I can't eat anything at all and I can only drink water! I'm terrified of doing something wrong! Help!! I'm so overwhelmed trying to make a grocery list.