I did an accident that was luckily caught by a staff member, so I have been working at my current nursery previously for 3 years but only been qualified since Christmas. Anyway I happened to accidentally let a unknown grandparent in as I thought it was a parent I knew and I didn’t but should of looked properly but I was in a conversation at that current moment with a parent, a parent buzzed the video door bell into the room that i was standing in I looked out the door due to the door being near the outside of my nursery room and I caught the grandparent thinking it was another parent, anyway I buzzed them in as usual unlucky for me it was one of the grandparents picking up that hadn’t been before (I have had multiple instances where I didn’t know the parent as had to go ask password at the door) but as I was in conversation with a parent I didn’t catch the grand parent coming into the room, my supervisor caught this and asked for the password immediately before letting the child go to grandparent. Although my manager has dismissed this as a mistake I can’t seem to get the thought out of my head how bad I feel, it’s just awful and as bad as it sounds although I know the safeguarding policies I should just never answer the door again and I’m now stressed that my co workers are all gonna treat me differently around opening the door etc although I know I’m capable and my manager hasn’t given me other than a verbal warning and quizzed me on a variety of safeguarding questions/ open door policies. It’s really put my confidence down and I’m definitely gonna be more careful, I’m just now really down cause I already thought I was shit at my job now I just feel more shit I never see any staff member making mistakes like me even if I have been their longer than one of them she never makes mistakes not serious ones.