Pul Tb is caused by a bacteria which enters the body primarily through airways. Though smoking
and excessive alcohol can weaken a person`s defenses but are not the main cause of contracting tb. You did not take your tb medicines regularly last time hence it may have got reactivated. Tb medicines do have some side effects and a person may feel week in the beginning but as the treatment is continued, these subside and patient starts feeling very good. This time do not stop treatment on your own as then there are chances of developing drug resistant tb for which treatment is very cumbersome.