Thank you for your patience. These bumps on his neck do sound interesting in that that sound quite prominent, but they aren't itchy to Scooby. Given he went to the groomer on Monday, then these could quite easily be due to clipper rash, however we also have to consider whether these could be to an allergic reaction, fleas or mites, or something else altogether.
You will need to continue to keep a close eye on the area, and probably the most important thing of all is to ensure Scooby doesn't start scratching the area. If he does, then the area will quickly become much, much more inflammed, and could even form a 'hot spot'. Firstly, make sure Scooby is up to date with his flea and worming treatments. Be sure to use a reliable product for this such as Advantage or Advocate, or one of the newer treatments such as Nexguard. Intestinal deworming treatments are important - but unrelated to this - so use a good allwormer like Drontal or Milbemax for this.
For the Benadryl, I'm not sure how much you were giving, but the typical dose is 1mg per pound of body weight up to twice daily. You can read more about the use of Benadryl in dogs online here: http://www.petplace.com/article/drug-library/library/over-the-counter/diphenhydramine-benadryl . He can potentially even have this every 8 hours (ie 3 times per day). See how he goes on this dosage, and if you were giving less than this, then you could give him one of these 'normal' dose amounts this evening.
You can also gently wash these area with some warm salty water as this will help to dry the area out. For this, just mix one teaspoon of salt per cup of luke warm water and use this to gently bathe the area. You could then gently dry the area and apply a little neosporin twice a day.
If there is not change in the area by Tuesday, definitely get your boy to the vet as they will need to carry some diagnostics out on the area to rule out mites or an underlying allergy. All the best with Scooby and hopefully this area settles in the next 24 - 48 hours or so. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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