Wadee' Assaf

It depends on what university u have applied for.. normally between 2-4 weeks

Contact with ur institution or with ur agent first! And u urself can contact EMGS to ask about that.. in short, you should know why you have been rejected, it could be some missing papers/documents

You should feel free to ask your University about ur visa and about ur application status. It could be that EMGS needs more documents! And thats why u should keep in contact with ur institution!!
Now for ur question it could take from 1-3 months depending on what university u applied for.

Contact your institution or your agent if its at pending status!
And I’m sorry to say this, if your application status is 15% as you said you will not be able to catch up with ur school in the end of this month! You still gonna wait more.