Oh dear, oh dear! But at least it has been landed with wings level and under some sort of control. Do you know how many passengers and what was approx. take-off weight? Assuming you have reached about 82 knots and have a little height, you should be able to climb slowly on one engine as long as you get the gear up and feather the appropriate motor. But it is not so easy to identify the problem engine if it has suffered only a partial power loss...a failed cylinder for example. But in that case it is better to leave it running until more altitude and airspeed is gained...etc, etc.