Need to have a colposcopy and frightened

I had a cervical smear 10 days ago and have already had a letter for a hospital appointment for a colposcopy as they have found cahnges. 
I'm not one to stress but am! I have recently had canges normaly around 5 days before my monthly of very light bleeding could this be an early sign?, I'm 36 no kids, don't drink, smoke. The opponent is next week so only just over 2.5 weeks from the smear test, what worries me more so being so quick! 
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