My players are getting weakened! What should I do? I don't want them to die! I dont have much food left later! AAAH!

It sounds like your villagers need more food. Starvation will cause your villagers to weaken from lack of food. The only thing that will help them is to build their food supply back up. You can look for mushrooms and have the children pick them to help get food until you have other food sources. In the early stages of the game, it's important not to increase your population until you have a more reliable food supply.

Okay well I'm probobly starting over

Make sure you have a few of the tech completed before increasing your population.

Also, don't keep them at the tech table all the time. They have to wonder, get food, swiming, relax. All work and no play weakens them. I learned that "almost" the hard way in my current hard game.