It's possible, but not certain. Many females can exhibit symptoms like those you have described after their heat cycle. As you are probably aware by now, it is VERY crucial to keep the female separated from any males during their heat cycle to prevent these types of "accidents"--easier said than done, I know as they can be very persistant little buggers once they have their minds set on something.
In addition, leaving a male and female to tie w/out supervision is VERY dangerous for both of them and could result in very SERIOUS injury...but I'm sure you already know that as you have offered your boy for stud before. (never hurts to reinforce the facts though
)
As far as the specific concerns you mentioned, yes, there are dangers. For starters, she is very young--it's never ideal to breed a female under 1 1/2 years. Genetics don't play a role in how many pups she will carry, so how many her mother whelped is irrelevant. The number of times that they tied, the sperm of your male, etc ARE factors.
My suggestion, which I know is not the one you would want to hear, would be to take your girl and have her spayed now to eliminate the possibility of a preganancy. Truth be told, if your girl is not even a year old, she has still got some growing to do. At already over 7 pounds, she is likely to be considerably over the weight standard for the breed and probably should NOT be bred at all.
However, my gut tells me that you would not want to do that, so my 2nd suggestion would be to prepare as if she WERE expecting. Find an experienced breeder in your area that would be willing to help you along the way, and give you a hand during her whelp.
I will keep my fingers crossed for your girl and hope that since your male failed to 'seal the deal' with his past suitors, that this instance was no different. For both your girls sake and yours! It is clearly obvious that you are not prepared to take on breeding at this time--regarding both experience and overall knowledge of the breed itself (i.e., there is no such thing as a teacup). (As were we all at some point.) If you really want to become a serious breeder, allow youself plenty of time to study under a mentor, tested and beome familiar w/ the breed standards until you know them frontwards and backwards in your sleep, all BEFORE breeding. THEN research and obtain quality dogs for breeding stock. Being as knowledgeable as possible is the only way to go and you will not regret taking the time to prepare yourself properly. IMO, any steps you can take towards producing quality dogs from your breedings and taking the neccessary steps to proceed in the safest, healthiest way possible for your dogs in what differentiates a GOOD breeder from a BAD one.
Good luck and keep us updated.