Is it O.K. to get another puppy?

We got a Toy poodle at the age of 2 months and we had her for a year and 6 months. She LOVES cats and other dogs, but just not big dogs. She mostly hates pit bulls but in LOVE with other dogs. We were thinking about getting another dog. Shes ok with other dogs coming over but then they usually leave to go home, but if we get another dog it will never leave. My dog (missy) is dominant and will growl at other dogs to protect her treats. She also gets jealous if we cuddle with other dogs. We don't know whats best.