my dd was frustrated for the first 7 months of her life, literally, and then she learned to crawl and was SO MUCH HAPPIER. it was like she had been here before and was trapped in a baby body, hahahaha. no seriously it was.

hang in there, just try to change the setting frequently, and it can sometimes get worse before it gets better, at 4 months my dd learned to roll onto her tummy and couldn't get back, you spend your days turning them back only for them to turn back over again... WHAT FUN!

does she like music, maybe try some different styles.. also the don't just have to play with toys, some random household objects often make the most interesting toys. hang in there she might be happier once she's mobile.