Have you considered renting out your current home? However, if you do this, you need to make sure (check with a lender) you could still qualify for the purchase of another home (taking into account the rental income you would have from renting your current home).
Now, if you want to flat out sell your current home and you owe more on it than what it would sell for, that is a Short Sale. It doesn't sound like your current home would 'qualify' for a short sale because one of the main qualifiers is that you have a financial hardship you can prove. Since you state you can make your current payments, this would 'disqualify' you.
So, maybe renting out your current home would be a viable option?