I agree with the above post. I can't help wonder if you might be having some hyperthyroidism going on. That will certainly cause the weight loss you are experiencing. Please see your doctor asap, as hyperthyroidism can cause other issues that could be dangerous.
You really need to go to the doctor. I would start there first. That's a lot of weight to lose without trying. Are you working a new job or exercising more than usual? Even if you were it is a lot of weight to lose in three months.