Should I worry about a lump on my puppy's head? When to see a vet?

Head trauma is always a cause for concern. Since this happened yesterday, there should have been some improvement with your pup if he suffered an injury such as a mild concussion. Sleeping a lot is not so much of a concern since young puppies normally sleep most of the day, but if you also see signs such as unresponsiveness, a head tilt, circling while walking, unequal pupil size, twitching of the eyes, ataxia (wobbly gait) or [vomiting](https://www.petcoach.co/dog/condition/vomiting-1/) then he should be [seen by a veterinarian immediately](https://www.petcoach.co/article/how-to-handle-a-pet-emergency/). If there is a bump, it may be a seroma (blood filled sac). This can treated by your veterinarian by either draining the area or trying a veterinary anti-inflammatory medication. Do not medicate him with anything OTC without the advice of your veterinarian as [many OTC drugs can be toxic](https://www.petcoach.co/article/7-human-medications-that-are-dangerous-for-your-pet) to dogs.

This could just be a normal formation of your dog skull. If it is not getting bigger, does not feel like it has fluid in it and there is no discharge I would recommend just measuring it once a day for about a week and seeing if it truly is getting bigger or not. If it is not it's likely a normal skull developing. If it is getting bigger then have your veterinarian take a look.

I would recommend that you have this lump checked out by a vet. There could be several different causes, but if this lump has been present for a while now it may indicate something very serious, like a defect in the skull. If it has only been there recently, it could be caused by swelling from trauma, insect bite, infection, among a few others. After thorough examination, the vet may recommend diagnostics such as x-rays or cytology to determine what is causing Pandora's lump.

My concern would be that the other dog may have bitten Hope on the head. Keep an eye on the swelling. If it is getting larger, if it starts to leak fluid, or if she isn't going back to a normal attitude when she wakes up from her nap, she needs to be examined by a vet right away as brain swelling could be fatal.

That's quite a lump! If it is growing rapidly or is painful, then Smoke should be seen by your veterinarian or at the nearest veterinary ER as soon as you can get him in. The same can be said if he is lethargic or unresponsive. If he is behaving normally and the lump is not bothering him, you can wait until tomorrow morning to have him seen by your vet.

It is usually cause by hitting the head on something hard or bu an insect bite. monitor it for 3-4 days to make sure the swelling is going down, if it doesn't please take him to your vet in order to get it checked.

Your puppy is plenty old enough to get started on her vaccinations, so taking her to the vet shouldn't be a problem. If she's acting fine and the bump is improving, then I wouldn't worry about it too much. She may have just banged herself hard enough to get a swelling. If she isn't acting like herself, then I recommend getting her to see the vet right away.