Am I eating enough

I am at Week 19 and only managed to eat 2 meals per day as I slept longer than usual and always missed my breakfast. I tend to endure hunger due to work and probably I only able to have 1 or 2 small snacks per day. Will it pose any health risk to my baby? My weight goes up and down by 1kg every 1-2 days and now it seems to go back to my weight 2 weeks before. Not sure how should I manage so I am eating enough yet not eating too much.