The answer is yes and no. In one sense they serve the same purpose. However some recent cases suggest that it is easier to get a post nup invalidated. If your the spouse with the assets get a prenup. If your the spouse without assets get a post nup
You should have received invoices from the old firm showing how much of your 5,000 was spent. Ask for an invoice and for the balance remaining to be refunded. You have the right to switch attorneys and firms. Depending on how much income your spouse makes you may be able to get him/her to pay for your attorney fees.
There are a bunch of documents that need to be filed to effectuate the divorce. Ask your attorney exactly what the status is. Once all papers are filed in Nassau County I've seen it take at least 4 months before the judgment if divorce is signed