how long do I have to file a malpractice lawsuit?

It is likely that you are limited to 2 years from the date of harm/injury.  However, if you did not find out about the injury/harm until later, then you may have more time.  When the statute of limitations begins to run can often he a difficult question to answer.  Thus, I recommend gathering all your medical records related to this and then finding an attorney to review them for  you.  Most consultations are free.  Best of luck.  NOTE:  This response is general in nature and should not be considered legal advice.  No attorney-client relationship exists and none is formed by this response.