Mental Torture in work place

I am working in a private IT company. I have some problems problems at office. I am an iOS developer. We have android team also. we both have the same projects but the android has 3 developers while i am the only guy in my team.I have the same projects as that of the android too. The company is making me work like hell to meet with the dead line. November end my teammate resigned due to low salary and heavy work load. From that day till 2 weeks back I have been working all the projects and now they are telling everyone in office that i am not working good since the projects are not yet over.They are telling everyone in office that I am not working and the android team is working well.Android is working well because they have more number of people to handle the projects and they also have testing devices. They also have 2 other people who can help them if they want help.So it makes it 5 in the team.They have been making me work everyday late night.Mentally they are torturing me. Secondly I asked for a testing device for 2 months and i got it only 2 weeks back. I couldn't work well without a testing device because a testing device is important for mobile app development. Thirdly I am given a salary of 6000 rupees after all this work. Fourth,my company has a training wing where i learned this development. They haven't given me the certificate of that training even after 3 months of completion of it. I paid a big amount for the training to the company almost 25000. If i file a case,is it legally valid?