No. It shouldn't happen. These 'antennae' you are describing are actualy the gourami's ventral fins. If they have broken or been shortened, the fish has either injured itself or been nipped. Make sure the wound is not ifnected. Though they do grow back, an infected fin can end up killing the fish. Also, they don't always grow back to their full length. Though these 'feelers' are important for the fish, not having full-length ones should not hinder it. Just make sure the water's very clean and your fish will be find (but try to work out what caused the injury to begin with and correct it).