The Prophet's ﷺ bed was about the size of the space in which a person is placed in his grave, and the prayer area was beside his head.
حدثنا مسدد حدثنا حماد عن خالد الحذاء عن أبي قلابة
كان فراش النبي ﷺ نحوا مما يوضع الإنسان في قبره وكان المسجد عند رأسه
No references are available.
[Its isnad is daif] It is found in Musnad Musaddad as in Matalib Aliyah: 2/397, hadith no. 2566. Some of the family members of Umm Salama are unknown.