Is it okay for a puppy to be vaccinated twice in one or two months?

I bought a three month old dalmatian puppy (female) from a guy a few days ago. He said that he already had her vaccinated with anti-rabies, anti-parvo etc (5in1 shot), but I still haven't got proof, and even if I had the papers for it, there's still a chance that it's another dog that got the shot after all. My mom said that we should just give her another shot just to be sure. Is that okay?

The only person who can safely answer that question is your vet. Just call the office and ask them, they will be glad to help.

A 3 month old puppy likely has NOT had a rabies vaccine- most vets won't administer them until 4-6 months of age. Take your pup in for a checkup and talk to the vet about risks associated with over-vaccination and what your options are. The vet can do a blood test called a titre to test immunities to different diseases, and should be able to tell from that if she has been vaccinated or not, but it can be a little costly to have it done.