Maintenance case issue.

My name is Dudam Rathamma .I need a legal advice regarding the maintenance from my husband.I have got married in 1993 and my husband had left me after 3 years of my marriage in 1995 and am blessed with a son who is of 2 years at that time and theb he married another woman. He is an state government employee in telangana state RTC. So i have filed a petition for the maintenance amount for my needs in 2010 and the Honorable district judge has sanctioned the amount of rs.3500/mon. In 2013, his salary was increased and .so i have filed a petition to enhance the amount to rs.7000 in the district court in the year 2013.As per june 2015 records,he is getting the salary of rs.30000 per month and now we are in oct 2016. As for the grace of God,the Honorable district court judge has enhanced the maintenance amount to Rs.7000/month and gave the Judgement as "The petitioner is granted enhancement of amount from Rs.2000 to rs.7000/-month FROM THE DATE OF ORDER".Actually i have filed this case in the sept,2013 and this case has ran for 3 years and got the judgement on sept 29,2016.So my question is that "Can i file an another petition to enhance the amount from the Date of petition or to enhance the amount from the date of his salary increase i.e.,June 2015?" Please help me with this issue and i request you to please furnish the phone number or a mail Id of the lawyer of the further clarifications. My mail Id is : dileepkumar9030@gmail.com. Thank You.