Hi Mum2boy i had similar concerns with Alex around that age and even now he has days were he wants someone to play with him all day but i think that we sometimes compare them to other children who aren't as lucky as ours to have someone able to give so much time to them. They are only little for such a short time and before you know it they will be embarrassed to be seen with mum. And i agree with Trish at this age they are very demanding.
Does he like drawing/painting as i find this is a good activity where i watch while doing other things but he is amusing himself with the colours.
Your doing a great job and are very lucky to have parents supporting you.