"After lunch,I felt at a loose end" means

From the passage,we learn that the writer was

"...now I was by myself it looked very large".The word 'it' here refers to

He did not look after the rest of the flat because

After lunch,I felt at a loose end and roamed about the little flat.It suited us well when mother was with me,but now I was by myself it was too large and I'd moved the dining room table into my bed room.That was now the only room I used,it had all the furniture I needed,a brass bedstead,a dressing table,some cane chairs whose seats were more or less caved in,a wardrobe with  a tarnished mirror.The rest of the flat was never used,so I didn't trouble to look after it.

The flat did not really suit him any more because

When the author says 'all would be well' he says