Serious question...please respond if you can.

I am 12 weeks 3 days with twins. This is my second pregnancy and so far it is 199% different than my first one with my son. I am finding that I have to eat every 2-3 hours, does that sound strange to anyone? Like my stomach is literally EMPTY after a couple hours and if I don't eat I am sick. I am just wondering if this is normal at this stage in a multiple pregnancy or if any of you ladies are experiencing something similar. Thanks :)