wrong

Assalamu alaikum  I am a medical student and for the past year or so I would sometimes need to pray zuhur in the hospital.Recently I discovered I was praying in the wrong direction....ie.I would pray slanting to my left while the qiblah was slanting to the right.What is the situation of my prayers with the incorrect qiblah,and must I repeat them ? The local mosque in the hospital has its qibla oriented in this wrong direction as well.And how far off must one be to be considered not directed correctly to the qiblah?Jazakum Allah khairan barak Allahu fikum for this wonderful service.May we all be dwellers of His Jannah in shaa Allah..