i recently had a crb check for my employment, a fine and conviction i had 14 years ago showed up. will this jeoperdise my job even though i have been employed there for 7 years?
Depends - the initial job application may have asked you a question you didn't truthfully answer. If that's the case, you've rendered your contract void and could face the sack. However, reasonable employers would most likely take your 7 years into account first.
it will depend on your job and or employers and what the conviction wwass for.
Eg if the conviction was for sexual offences and you now work in a nursery you're pretty much scuppered!
c'mon, tell us what you done!