OPT/ CPT/ Employment

Hi everyone! I have a complicated situation regarding my status. I came to United States as a B2 visitor visa. I entered US last time on July 24th 2017. According to my i94 I was admitted until January 24th 2018. My authorized stay was valid until January 24th 2018. Then circumstances changed and I got married. My wife was completing her OPT when we got married and She had F1 visa valid until February 20th 2019. After marriage, I decided to stay with my wife until completion of her OPT. So, on January 11th I applied for the extension of my stay and also for the change of status from B2 to F1. During this time, My Wife’s employer offered her H1b which She accepted. Her H1 was approved and it started from October 1st 2018. I did not get any response from USCIS till then. I was confused and filed another application on September 28th for the change of status from F2 pending status to H4. Meanwhile, It took USCIS 10 months to process my applications. In October I got RFE for both extension of stay and change of status from B2 to F2. I sent the response and got extension of stay approved until July 24th 2018 on November 6th 2018. A month later on December 4th USCIS rejected change of status application having reason that My Wife’s F1 status is completed on October 1st 2018 so they cannot approve my application. I timely applied for the extension of stay and changed of status from B2 to F2. I didn’t know USCIS will take more than 10 months to take a decision. I was hoping that my F2 application will be approved far before October 1st and then I would be able to apply for change of status from F2 to H4. Now when USCIs has denied my application, my unauthorized stay has begun from July 24th 2018. I do not know what to do in this situation. Should I go back and apply for H4 or is there a possibility of changing this decision. On letter it is written that I should leave country in 33 days upon receipt of this letter. I do not feel comfortable to go back and reapply for H4. I have a professional exam scheduled here on December 20th 2018. Please guide me if somebody have had been in a similar situation. What are my options and what should I do. I can consult with a lawyer if they guarantee that my stay here in US will not affect my future visa applications or when I return to my country.
Thanks.