Landlord's Electrial Safety Check

Other

Hi. I'm pretty new to being a landlord having invested in a few houses last year, so apologies if this seems like a basic query. I had an NICEIC electrial contractor do a complete landlord's electrical safety check on one of my houses last November at the cost of £120.00 plus VAT. I was told that the paperwork issued would be valid for 5 years. My tenant moved in to the house in mid-December. However, I've just found out that the tenant (who is not an electrician) has personally changed at least one of the light fittings in the property and made reference to 'taking apart the extractor fan' too. From what I understand these alterations were purely cosmetic and weren't needed due to faults. I understand that these are minor jobs which a lot of people CAN do themselves in their OWN home but I'm unhappy that they've been done without a proper NICEIC registered electrician in my property. So the crux of my question is: DOES THE FACT THAT ELECTRICAL ALTERATIONS HAVE NOW BEEN CARRIED OUT (WITHOUT MY PRIOR KNOWLEDGE) IN THE PROPERTY BY THE TENANT (WHO IS NOT A QUALIFIED ELECTRICIAN) INVALIDATE MY ELECTRICAL SAFETY PAPERWORK? I'm hope I'm not overreacting... I'm aware that the Electrical Safety check isn't strictly 'law' like the annual Gas Safety Certificate is but I still want to make sure I keep things water-tight on the legal front with these houses and do not wish to find myself being blamed at any point in the future for problems arrising from what the tenant has done. Thanks very much in advance for your advice.