It's hard to change my diet since just finding out I'm pregnant

What are the best foods to eat when your pregnant ? I'm finding it very hard to stop my habit of eating fast food and dining out and eating along with eating my favorite junk food and also drinking soda juice and my Starbucks to be honest all the people that I know they were pregnant it didn't seem like they were eating too healthy they were doing what they were doing before they were pregnant I love my food but at the same time after every time that I eat I feel like a pig and think I'm being selfish towards the baby I am taking my prenatal vitamins though