Nutella that's annoying about the doctor! Hope your DS is feeling a bit better by now. My Ds1 used to get croup every autumn, and was very wheezy (to the point people used to stop and ask me if he should be out of bed) every time he got a cold - to which he was very prone. Finally (touch wood) he seems to have grown out of both this year, at 6 and a bit, a year later than the doctors told me he would - his lung function tests have always been normal to better than average, which is how they rule out asthma.
I could leave DS1 to play for a bit from about 18 months, but only if I'd "walked" him first - I used to drop DD off at Kindergarten then walk him to the next village and back (about 4km altogether) - he had to be on his running bike or pedal tractor, he wouldn't actually walk and pushing him in a buggy was worse than pointless. As long as I did that he would then play in quite a contented, self contained way for the remaining hour DD was at KiGa and I got stuff done. Both DD and DS2 are totally different though - physical exercise made no odds to how demanding DD was, she wanted constant interaction and still does at age 8 tbh - the difference now (and since about age 4 tbh) is that she can have friends around, so she doesn't need me , and being able to read helps a lot too, as that's something she will get absorbed in. She has never played alone though, not ever. Having a brother close in age also helped from when they were about 4 and 2, as from then they would play together, also meaning less intense demands on me. At 2 and 7 months DS2 is like DD - he plays alone a bit, building with Duplo or playing Playmobile or with cars, or drawing, but only if I am chatting to him the whole time, I certainly can't be in a different room. Siblings help. But they also fight and the boys are so wild together (its actually amazing how physically wild, and how loud, their happy play is - totally different to the way DD and DS1 play when its the 2 DSs) even in their happy play that somebody often ends up in tears...
DS2 is at Kinderpark now - like drop off playgroup. He loves it (I never managed to settle either of the older ones in there, but he started asking to stay with DS1 at KiGa so I thought I'd try) so now I get two 2.5 hour blocks a week child free in term time, which is very useful, if only for MNing putting laundry away!
Bertie our house was just advertised in the paper - I was surprised to discover you can search our local paper's adverts online (hardly anything is online locally, but the adverts from the paper are!) its a good way to find something provisionfrei and often cheaper rent.