Help..am I going crazy..?

The past few months I've been seeing and hearing things..I try to ignore it but its getting worse.. 4 example..I work in a hospital..and for a few weeks I had been looking after this elderly lady..she was lovely..and 1 night I was on my way home..and I was walking down a corridor towards the car park..and an elderly man was walking beside me.. I was getting creaped out cos he didn't say anything..he just kept smiling..then he asked me where room 702 was..and I went to look at him and he was gone..so I just stood there 4 about 5 minutes cos I thought I was going nuts..cos there was no where he could have gone that quick..then I realised that was the room number of the lady I had been looking after..so I went up there..and they told me she had just ped away 5 minutes ago..and that's only 1 of them..its scaring me..