Do you also smoke? Smokers can have more problems with asbestos fibres in the longer term.
This (American) site[/url] has details of the types of Asbestos in use, click the arrow in the box to scroll through them.
I think welsh farmer has confused his less and more in the first sentence, stuff over 30 years old is more likely to be contaminated with asbestos fibres. A sample sent to a testing lab would allow you to be more certain of what was in the sheet material. Costs are low for the test and there should be an asbestos log of the premises to consult listing what and where it is in the building. If there isn’t one, a call to HSE should be on your list for Monday.