16 week old puppy showing a lot of fear of other dogs

So I had an interesting weekend with my pups. I have a 16 week old golden as well as a 18 week old Beagle (I know getting 2 puppies isn't always the smartest thing), and everything has been going very well. Both dogs love each other and are doing well in their training. However this weekend a few issues have arisen. While I was walking Annie (the golden) we encountered quite a few others walking their dog, and everytime they came together she was extrememly timid and fearfull, so after the walk I took her to a friend who has a well trained Cocker, to give her some time with other dogs. During the 20 minutes I was there she was pretty much afraid of the Cocker the entire time. When the dog would approach her her tail would be fully tucked under her butt, and she would kind of run back away. By the end she was a little less fearful, but she was definately timid.
Then today we were out in the front yard playing and a neighbor dog came walking over, and as the other dog approached Annie barked at her and went out to meet her, when they met they sniffed a few times and the other dog ran back home. During the whole interaction, Annie's tail was wagging but her hackles were raised.
Annie has always been a very gentle dog, but this was more pronounced than usual. Just as an FYI, she doesn't have the same fear of humans, as she loves children and has no fear of approacking them. For adults she will be a little wary and approach slow with her head near the ground, but as soon as the person pets her, the fear leaves and she is in love. Anyway, is this somewhat normal for a young female pup? Any suggestions on how to handle it?
Thanks,