I wish I could give you an answer to this as I feel your pain. But, you will need to wait and see what your Mortgage Advisor tells you. It does not make any sense to me that if you only had one 30 day late recently that they would drop you for a loan. They look at the past 1 year history and common sense should come into play. But, it just all depends on who you are trying to get a loan from and what their requirements are.
I would hope that you where pre-qualified or just tying to get pre-qualfied and you did not already find a home. This is one of the major reasons why it is always best to get pre-qualified before you start looking for a home, to reduce the stress.
But, the worst thing that could happen to you right now is you will not get the loan and they will tell you what you need to do to get the loan from them. If it is a matter of getting your score up again...they can tell you fast ways to get your score up within 60 to 90 days. So, all hope is not lost. It just may mean waiting a few months before you start the home buying process.
So, your future looks bright no matter what the answer comes back to be at this point.
As long as you are walking toward your goal that is all that is important.
Good Luck to you.