Its just nature not an omen, small birds are exhausted from rearing chicks and every year there are large numbers who either die of old age, or fall prey to predators, and birds flying into windows is something that happens quite a lot Remeber runs of bad luck and misfortune always come to an end but if you look for negative signs you create a negative energy this seems to keep the cycle going although the scientific/logical atheists are now going to put on lots of posts sating that is rubbish. focus on being positive and imagine good energy filling your life... can't hurt, might help.