Yes, unless you filed a timely appeal or unless your rights under the Servicemembers Civil Relief Act were violated. You should consult both a JAG lawyer and (quickly) a civilian lawyer in the jurisdiction in which your divorce was granted.
Yes, as you present the facts, it is legally binding. If you are within the 30 days following entry, you can file a motion to reconsider and ask the court to consider the objections you filed with opposing counsel. Keep in mind that the motion to reconsider does not extend your time to appeal and you may have to file the appeal on the 30th day. You can also file a motion to set aside the final judgment on the basis of fraud if the presenting attorney did not notify the court of the objections. A motion to set aside may be appealed in its own right (or the denial thereof) but the other side MAY simply consent to modification rather than going through all of that. It all turns on the 30th day, though because after that date, the judgment is final unless it is set aside.
This response is for informational purposes only and may not be taken to create an attorney client relationship. If you wish to discus the particulars of your case, you should contact one of our family law attorneys in private to create or maintain any attorney client privilege.