<human>: Can you condense the text into a few key points?

Last summer I worked at an asbestos lab where my duties were to prep samples and analyze some of them.  Specifically, one of the responsibilities was to prepare larger samples that came in petri dishes and put them in tubes.  We had vents and set places to work at and I followed procedure all the time.  About a month of doing this kind of work (around 3 hours a day) I found out that the fan at the bench I was working on was a bit broken.  Apparently, when you turn it on all the way, the fan isn't actually on all the way (barely on) and to turn it on all the way, you had to move the switch about 3/4 of the way.  A month of doing this kind of work under a bad fan.  This is what scares me.  Some of the samples that I dealt with were very dirty and I know that some of them contained fibers because I know that some samples failed the tests.
I feel stupid that I didn't realize that the fan wasn't on all the way, but to be fair, I never heard it on all the way (its a lot louder when it is on 100%).  Because of this, I'm fairly sure that I must have breathed in some fibers.  Now, I also know that when you breathe in a fiber, it takes around 30-40 years for it to develop into lung cancer.  During this time it just stays in your lungs and your body cannot break it down.  They are microscopic pieces of rock. 
I don't see a point of living life "healthy" anymore.  I really feel like I will die in 30-40 years as a result of lung cancer because of this.  I don't feel like a doctor can help me now because I don't have any symptoms, the fiber would just be in my lung.  
My question is basically, am i wrong in that a doctor cannot help me?
<bot>: Worked at an asbestos lab with a fan that wasn't on all the way, I think I breathed in more than one fiber and will die as a result of lung cancer.  Can a doctor help me?