6 month sleep regression?!

Is there such a thing as a 6 month sleep regression? It's been four years since my daughter was baby so I don't remember.

He will be 6 months on the 7th but for the last 3-4 days he's been so irritable. Always crying unless he's being held. He's no longer sleeping well at night unless he's held. We can get maybe an hour and a half before he's up again. He doesn't want to nurse for long and he has the bare minimum number of wet diapers. I thought maybe teething but I don't feel any teeth trying to pop through. I brought him to the doctor's yesterday thinking someone this wrong with him as we are all getting over different illnesses but he's fine. Negative for strep, covid, and rsv. No fever. Lungs sound great. Oxygen and heart rate are perfect. Not dehydrated. Doctor said it's likely a viral thing and wait it out. But he really doesn't appear to be sick at all. I'm just at a loss. We are so tired. Not that it means much but the wonder weeks app says he's in leap 5 for the next 16 days