Allergic reaction to vaccinations?

My mom's dog hadn't been vaccinated for at least 5 years and I finally argued with her enough to take her in.But today I noticed that she had a spot that looked like she had been chewing on the back of her leg.I know animals can stretch to itch themselves but it was the back of her thigh, so I thought.. you know, she's a big dog, how would she reach back there to bite it??So I took a closer look and there are scabby bumps all over the inner and back part of her thigh.I immediately thought she has an allergic reaction to her vaccinations and got hives.But her vaccs were done Monday, last week. I hope it didn't go unnoticed for that long or is it possible that it just popped up?? I work at a vet's office so I have to check on dogs and puppies sometimes when they get vaccs to make sure, but that's only a course of a couple days and then they go home. So I'm not really sure.She's not a very hairy dog so I easily noticed it from a few feet away.Could it be hives from her vaccs???? The vet is closed on Sundays (tomorrow) so I won't be able to take her anywhere, and if it's not an emergency, I don't think it'd be necessary to call the emergency clinic.I know I sound kind of panicked but I'm honestly not really sure to do, and my mom kind of puts things off so I have to do it for the sake of the dog.Thank you for any answers!

dogs are able to take many types of human medications. if you have any benedryl give your dog some to see if this relives the "hives" it wont affect your dog in any other way (meaning if it's not an allergy your dog wont get sick from taking benedryl) i dont know how big your dog is but my great dane used to get allergic reactions to food that had corn in it. he was a small dane (140 lbs) and the vet said he could take a whole tablet of benedryl. if your dog is half that then give her half a tablet. i wouldnt give the dog a whole tablet unless she's at least 100lbs.i doubt very much it's from the vaccinations though. did the dog get a skin scraping taken? it could be from that. my dog had that done to his tail and he never grew the hair back after that. he had a red raw spot for about a month and then a bald patch after that.dont fret. if your dog isnt acting sick or in pain it's not an emergency.:)

Yes they can have reactions a good amount of time out. One of the many reasons I TITER TEST and do not over vaccinate. My dogs get their puppy shots and that is it, and I use Titer test to ensure the antigens level are well above the needed level. Any how that being another story, you can try Benedryl it is helpful for most allergic reactions. She could have had a reaction to the vaccines or something else. I have a large dog with allergies and he gets that area ALL the time. If they have an itch they can get it. Try the Benedryl and see if it gets better. use some soothing sprays like Richards Organic Incredible Skin Spray. That is the best it helps with itching and irritation and has natural antibiotic properties to avoid infection