guinea pig crying

lol it's not going to happen if it's what I think it is. if you stay very quiet and never let them know of your presence then the wheeking might subside. They only do it for you to get your attention and tell the rest of the heard that the human is coming and might give us stuff!

even the herd hearing my bed creak in the morning will send them into telling me about everything they need, before I've risen

It's probably not crying, but wheeking, which is the sound they make when they want attention or a snack. If it sounds like an actual cry, it's probably in pain and a vet visit is recommended.