Last night around 9:30 I felt SO HUNGRY, but I had already eaten all of my calories for the day.  I held out and didn't eat anything, but should I have?

It's certainly not the end of the world.  It's also not the end of the world to have a snack, either, so in that sense it's up to you.

Consistently refusing to eat when you're hungry can lead to problems, however.  Even in just the simple sense, it's really hard to stick to a diet where you're hungry and miserable all the time.  Additionally, if you let yourself get really hungry a lot, your reason and self control poop out and you're more likely to just give up and pig out on something terrible.

Usually if I'm really miserably hungry, I'll just eat something.  I just try really hard to eat something healthy, and something small.  In the end, though, no harm, no foul. 

I totally agree with the last poster, if im really starving and i've tried drinking a glass of water and im still really starving i do eat something. (Quite often i feel hungry when im actually thirsty so a glass of water fixes it)

Generally if i've dismissed thirst and im still starving i resort to a bowl of oatmeal (wow im on an oatmeal crusade today) 15g with 75mls skimmed milk and little cinamon or honey (tiny weenie bit) is about 100cals ...(about half the amount i have for breakfast) keeps me going for the rest of the evening.

Tbh i think if your starving its better to go 100 cals over budget than it is to spend the evening misrable and starving, as your more likely to just give up and eat something totally horrible for 600 cals.

Besides too many misrable starving days or more likely to make you give up on the whole diet... adding an extra 100 cals here or there the odd day really isn't gonig to hurt your wieght loss as generally most of us aim for a 500+ cal deficit.. 400cals is still a deficit after all.  

I totally agree, eating healthy stuff when hungry is the answer. Every night when i get in from work im clawing the wall cos im hungry. But I cant have my dinner straight away as my fella usually doesnt get hime till half 6 or half 7 so i wait till he gets in. But to see me through till then ill snack on something with low calories.

This might not interest you but I read a peice in mens health magazine which changed my way of eating. It said gerkins are the best thing for when your trying to lose weight as they have like 1-5 calories in a big gerkin and no fat. So you can snack on them without feeling guilty. If your not into gerkins tho theres carrots or fruit like raspberries. Just dont do what my mate does and binge on bad things. He went into his fridge and at a 500g block of cheese! I cant do that!!