YANBU
I am a single mum with one child too.
When DS was born (I was still with ex) and we lived in my lovely one bed flat that I loved. I felt huge pressure on me to move to a two bed (people are very judgemental so I know exactly where you are coming from).
So I moved to a 2 bed ex local authority house. On paper it seemed ok - two bed house, quite nice inside, own garden, in good school catchment.
Was the WORST move I ever made.
I HATED it. It was a long walk to get anywhere (no car) and although some of the neighbours were nice the ones you noticed were not. The local kids were rough and constantly in my garden, the police were out a lot and I just felt isolated and never felt safe.
Lasted there three years then sold the house losing a huge amount of money (as had bought it at the peak of market).
We moved back to a one bed flat (it does have a box room which is meant to be DS's room but he mainly chooses to sleep with me) in a more central location (as could not afford two bed) and I am so much happier.
People are so judgemental about my living situation but the bottom line is that not many single parents can afford the ideal accommodation that two parent familied can.
So long as you are happy I can say from experience that is so much more important than having two bedrooms
so enjoy feeding the ducks