First of all, let me say that Baby is just adorable. By all means, have her spayed to save her from potential serious health issues as she gets older. It's perfectly safe and she will be bouncing around within a few days after it's done - just as if nothing ever happened.
As for the licking - can't say for sure, but it sounds like seasonal allergies. I don't know where you live, but here in the Mid-Atlantic region of the U.S., this is the time of year when my dogs start experiencing the "itchies" more than what they have the rest of the year. I add Omega 3 fish oil to their meals year round and it helps to some degree, but doesn't eliminate the problem. Some find oatmeal baths to be helpful, but that never had much of an effect on my fur kids. Without extensive and expensive allergy testing, it's difficult to say exactly what the culprit is that causes this problem. Antihistimines such as Benedryl can be given with some success, but be sure to check doseage with your vet. When all else fails, they can get a steroid injection, but these are very potent and should only be given as a last resort for severe itching. Please stay away from oral steroids given on a regular basis as these can cause serious health issues. Years ago I took my 2 Lhasas to a vet that prescribed steroids to be taken daily. As a result they both developed diabetis (just one of the possible consequences of taking steroids for an extended period of time). And unfortunately this vet did not know how to properly manage diabetis either, so both dogs had other problems that developed because of this in spite of being on insulin every day.
Don't know if this helps any, but at least you might have some idea of what's going on with Ms Lickey Pup. Then again, maybe she just likes to lick - I also had one like that - I always said he had a foot fettish! Good Luck!