discrimination/harrassment???????

I feel dicriminated against and harrassed because I am a single parent. I work from 8am - 4pm. I have always had a problem with my job when it comes to working overtime. I do not have a problem working my shift but I am not able to work over 4 hours nor come in 4 hours early as they try to force upon me from time to time since I am raising my son alone. Not only do they try to force me to stay over or come in early but they give an hour notice. Who can get child care set up in an hours notice. All my family/grandparents are 1 hour away. My question is Do single parents have any type of rights when it comes to a job. I am always walking on eggshells because of this situation. My son is only 8 yrs old. I am the only on responsible for his transportation to and from school/ sports, doctor appt. dentist appt. his overall well being. Please advise

see your other post

I have filed a complain for discrimination/harrassment whith the Civil Rights Commission against the company I work for, I want to know my rights in this situation.