Welcome to the group . . . .
I guess that my best advice is for you to think about what is going on in your life . . . .
You are having difficult times with your business which is stressful and can cause anxiety which, in turn, can produce physical symptoms which, in turn, trigger more anxiety and so you get entrenched in a cycle.
Also, you did something that physically probably aggravated your back and so that is now adding another layer on to the stress and anxiety.
If you have been to a doctor and you feel that the doctor is reliable and she or he told you that it was muscle damage, then you need to accept that. If, however, you are not convinced, then perhaps you need a second opinion. If you were helping friends lift a car, I could see that action would cause muscle issues.
I would also not recommend that you drink beer with pain killers. Beer, for folks with anxiety, can itself increase anxiety or become an addiction which is simply adding more issues to the anxiety. If the meds are not working, then you need to speak with your doctor again.
I do not know how the health care system operates in Malaysia, but I think that you need counseling to deal with the anxiety from your financial issues which seems to be the immediate trigger. Do you have access to any community-based support groups or a circle of families or friends who could help you deal with your anxiety? You would still benefit from a professional counselor but sometimes a strong circle of support can work wonders while you are going through the rough times . . . I am sorry that I can't be of more help, but check back as others may have better information or suggestions . . .take care, kc