Can I file a petition for modification for child support since my husband’s income is now higher?

You can file an Order to Show Cause (court form) requesting a modification of child support.  Changed circumstances such as a change in income would be grounds for a modification of child support.  You would also file a supporting declaration stating the facts in support of your request for a modification of child support.  With these documents, file a proof of service and serve a copy of your documents by mail on your ex.  When you file your Order to Show Cause, the court will schedule a hearing on the issue of a modification of child support.  You can file now and at the hearing raise the issues of the overtime, the increased pay from the new contracts, the retroactive pay.  You should also include these issues in your supporting declaration.  Your supporting declaration states the facts in support of your request for a modification of child support.  File your documents with the court in the county where the original case was filed. If you are able to obtain a current income and expense declaration from your ex, that will provide additional evidence of the increase in income supporting your request for a modification of child support.  If you aren't able to obtain a current income and expesne declaration from your ex, file the other documents mentioned above without it.

The proof of service verifies the date of mailing to your ex the documents you have filed with the court.  You can either use a court form proof of service or you can write your own.  If you write your own proof of service, it just says that you are at least eighteen years of age and the attached documents were sent via first class mail unless stated otherwise to ________ (name and address of your ex) on ________ (date).  You sign and date at the bottom.  The date you sign should be the same as the date of mailing and the same date you file your documents with the court.