You do not have to really worry about the medical fitness certificate as

The medical college you are going to get in counselling have its own teaching hospital

And you will have a medical check up there itself at the time of admission and do not worry it's just a formality unless you have really big issues such has handicapped , colour blindness , etc

And trust me , you will enjoy your check up as you will first time see your hospital , you will be treated as special guest , you will stand out of line , will be attended first and completely free , you will get a feel of a doctor

And in case you want to be too sure , you can get fitness certificate from any Gov. Hospital .