Q.My seedlings are falling over
My seedlings are falling over. Should I replant them in a bigger pot almost up to the leaves to hold them up?

It sounds like you have leggy (tall and floppy) seedlings. As the article below will discuss, you should move your seedlings closer to a light source and lightly brush your hand over the tops of the seedlings (or have an oscillating fan gently blow on them a few hours a day) to strengthen and thicken them. It also won't hurt to carefully add more soil around them - if you have room. You can also transplant them into a bigger plant if they are in dire straits of tipping over completely.
https://www.gardeningknowhow.com/garden-how-to/seeds/leggy-seedling.htm