Vitamins with iron va without iron?

I take first response gummies that don't have iron in them and my Dr advised me to switch so I switched to materna with DHA pills. Since I took them I felt nauseated every day and my stomach killed me digestion wise. I switched back to my gummies to see if it was the vitamins and it was. My appetite has already changed enough and I don't need my symptoms to get in the way of me doing what I have to do for school and finishing in the next month or two for my certificate. Has anyone else managed just fine without vitamins with iron in them? I eat meat almost every day but I know I could use more veggies. Thanks in advance 🙏☺️