They are too young to be house trained well enough to leave them on the bed. They are also too small to be able to comfortably get down from the bed to let you know they need to go potty. (A puppy this size can break a leg jumping off a bed!)
Also, puppies generally like to pee on absorbent surfaces.
So there is nothing wrong with cuddling them on the bed for short times, but be sure they went potty before you bring them up on the bed and don't keep them there too long.
Puppies this young need to pee very often, just after waking up, after eating and drinking, and after or even during play time.
Remember, NEVER yell at or even scold a puppy for a potty accident. You will only frighten the puppy and teach them to hide when going potty. Accidents are the result of the human not properly managing the situation. It is your job, as the human, to take the puppies out to tinkle really, really often. They cannot tell you yet that they need to go. Also, they do not understand that it is "wrong" for them to potty inside, so you cannot blame them.
Follow these directions for house training
them and they will be reliable in a few weeks or a couple of months.
Good luck with your little babies!
Oh, one more thing, try to do a better job managing the situation with the older dog as well, so the older dog is not frightening the puppies. That does not mean you should scold your other dog, which would just teach the older dog to hate the puppies. Instead, use baby gates and other management strategies to prevent the puppies from bothering the older dog and make sure your older dog still gets plenty of your attention too.