All seeds are failing

[Lucy El Sherif]

Hi
I have been trying to grow plants from seeds in pots at home(vegetables and
flowers, actually) and all of them grow very fast after sprouting, then they
bend over with their weight (about 2 inches/4cms) every single time!
Does anyone have any idea what I may be doing wrong? I give them plenty of
water (not too much, though, and adequate drainage and clay pots) plenty of
light.  What could it be?
Thanks!
Lucy