Do I need an electrician?

The most simple way to explain this is a licensed electrician will  need to be called if you require work on or behind anything to do with light switches , installation of light fittings/fans that has to be hard wired, power outlets and switchboards.

Apart from being the law and being very dangerous , if you do have an issue with your fitting or fan and you have not used a licensed electrician you may void your warranty  as proof of insulation is required for warranty claims.