Non-compete clause validity for a subcontractor

I worked for a consulting firm with no maternity leave policy. The firm only offered to hold the job for 90 days. I started working in August 1999 and at the end of my maternity leave (Nov 2002) i was unable to come back to work full-time and had to resign. In December 2002 my clients asked for me to come back, so my firm offered to hire me as a subcontractor with NO benefits, working for a cut but with flexible hours as long as i got the work done. I was being severely underpaid considering my qualifications (2 Masters), but owing to our financial situation i took it. As part of the subcontractor contract i signed a "no-compete" clause.
For the past 14 years i have continued working under it at a low pay, i lost my seniority the day i went on maternity leave and hold the same title as i did 14 years ago. I was unable to move due to my child having major medical issues.
I am finally fed-up at the work environment (i am expected to report to new hires with 2 years experience when compared to my 18 years) and i want to quit. I am set up as an s-corp on my own. I know if i quit my clients will offer to hire me, but i am concerned about the "no-compete" i signed 14 years ago. That document does not include any expiry date from what i see.
If i quit and get hired by one of my clients, can the company come after me?
Secondly, the contract was signed with the company's owner who recently sold the company. Am i still bound by it.
In the past 10 years several; employees have joined and quit the firm and walked away with client accts. but the firm has never pursued any of them...can and will they sue me?
I am a minority colored immigrant if that makes any difference.

I am in a turmoil and increasingly miserable. Can you provide some guidance? I live in Michigan.