You first need to determine the cause for the vomiting. If your dog has not seen the vet recently for a fecal exam, I would do this first to rule out parasites as the cause. Coccidia and giardia (two protozoan concerns) are also a problem in puppies.
Your vet can recommend some immodium to help with the vomiting but you really need to find the cause before you give him anything.
Until you can see the vet, I suggest that you hold off on food or switch her over to a bland diet of just boiled chicken and white rice in very small amounts.
Most often this is caused by a simple parasite problem or coccidia or giardia. You can find out with a simple fecal exam.
Intestinal obstructions can cause vomiting so you should keep a close eye on this.
Let me know if you still have questions.
You really can't tell about an intestinal obstruction from the outside. You just keep an eye on your dog and should see the vet if you see vomiting, lethargy, diarrhea, etc, because all of these are symptoms.
I would hold off on food for the next few hours. Then offer her a small bit (1 tsp) of the bland food (chicken and rice mixture) and see if she keeps it down. If she can, offer more at the next feeding.
At this age, you should also talk with your vet about reflux disease. Sometimes an abundance of stomach acid can cause some irritation.