Can someone clear up uk driving test rules?

Hello. I might be looking for excuses but im pretty sure that im being taken for a ride! I failed my driving test last time as when going round a mini roundabout (turning right) my back drivers side wheel touched (not went over) the white centre. Was told it was an instant fail? Had another yest and apparently got too close to a car coming in the opposite direction down a lane, now i am 200% thats a lie. I was dreading meeting a car going down that lane and was so relived i didnt!! Also tge arms on my glasses were too thick (they are standard glasses?? Nit exactly thick?!) would appreciate your thoughts