Talk to General Physician on Regular Intake Of Multivitamins(Surbex Z) In Teenage

I am a medical student living in hostel. Being a hostelite, it is difficult for me to eat a balanced diet. I started to have problems like hairloss and low energy levels. So I started using Surbex Z 3 months ago and started to feel better after. I want to ask: 1)Is it okay to take multivitamins at this age regularly? 2)Are there any dependency problems due to multivitamins? 3)Can I use multivitamins for long........ rest of my life?