Just because the Divorce Decree has been signed by the Judge doesn’t mean it’s final in Texas. If you “got screwed” in your divorce, it may be possible to undo the damage.
If you believe the other side took advantage of you or the Judge simply made the wrong decision, then you need to have your decree scrutinized by a lawyer right away. But the clock is ticking. A party generally has the right to file a Motion for New Trial within 30 days of the entry of the Decree.
If the Court grants the Motion, then the Judge may allow you to have another bite at the apple and get the result you believe you are entitled to. The Judge could order a Full New Trial, where the entire judgment is up to be changed. Or it could be for a Partial New Trial, where only the limited issue(s) would be heard again.
Sometimes the error in the Decree is obvious to the Judge, sometimes it is not. This is the first step in the appeals process. So if the New Trial doesn’t fix it, then you might want to consider the next steps in getting it to the Court of Appeals.