prenatals?

ok, really if you take prenatals they make you nauseated(if not actually puking) and constipated. my best friends doctor told her they aren't even really necessary and really only benefit the mom. and her daughter turned out great despite my friend not taking prenatals. my daughter turned out fine and I took one bottle of gummies my entire pregnancy. now its like the only time I've been able to -tmi- poop or wasn't sick to my stomach all day was the few days I forgot my prenatals. >_> I eat a balanced diet full of veggies and plant based protein. I'm really starting to feel like prenatals are a damn gimmick to get even more money out of parents during pregnancy and baby times. it's absolutely ridiculous to me. anyone know of a vegan, low iron prenatal that doesn't cost $30?