I agree with sweetaspie about the hair. Definitely get some layers and some highlights close to your natural colour so it's less maintenance. As for clothing where what you feel sexiest in. Show off your best features or which assets he loves best. Go on a little shopping trip and try on anything and everything that jumps out at you.
Your only 22, just because your a mom doesn't mean you have to dress like it! I am 23 and have a 1 year old and I feel like I don't dress like a mom. Of course you don't want to dress like a tramp but you can still dress sexy. You have two babies so I am guess on most days you aren't very dressed up when he comes home because 2 babies are a lot of work. Just try making a little special effort for when he comes home. As far as hair, highlights maybe? Some layers? I dunno, from what I can see of your picture you look pretty so I don't think you need a makeover. Maybe you are just stuck in a rut!