my dogs in heat if she is still bleeding is she pregnant?

 
My dogs in heat if she is still bleeding is she pregnant?
Well my dog way to young to get pregnant so it would be very dangerous for her and her puppies if she became pregnant she 7 month old, (beagle,shiz tu mix). I was wondering, she in heat and if she still bleeding can she be pregnant?
I assume knowing this, you didn't leave her unsupervised where an intact male could get to her. She's old enough to spay if there's any doubt and you didn't bother keeping her confined