Its normal.  The hormones that come with pregnancy do weird things to our bodies, including acting as an appetite suppressant and an appetite stimulant, just depends where you are in your pregnancy.

Smaller lighter snacks will help with this.  Avoid heavy foods like brown breads and lots of meat.  Try and eat chicken and fish instead.

One thing that will help you is plain salted chips (hot or crisps).  If it is all you can eat, then it is acceptable (I was given a prescription for Macca's any time i wanted it with my first! rofl).  they are easy to digest, provide much needed salts and easy to get a hold of, not to mention don't cost an arm and a leg.

it may be that bubs is squashin your stomach and so it cant hold as much as before...?

this happened to me as well towards the end of my prenancy just couldnt eat very much, i had to eat tiny portions but often to make sure i was gettin enough

I pretty much force fed myself as I knew I had to eat!  Couldn't even think of eating and I love my food!!  I had the healthiest, happiest baby - she just took up a lot of room!

I don't think it is a big deal, there isn't much room for food right now anyway... As long as you are getting plenty of fluids, (especially since it's summer) and nibble on nutrional bits and pieces here and there you should be fine.  Try some nice fresh fruit salads and nibble away at them as you feel a little hungry during the day.  They have plenty of energy and will be easily digested.

As your baby gets bigger it squashes all your insides including your stomach hence making the room in your stomach less. That is why you are not as hungry because it is taking less food to fill the gap in your stomach