Apart from Sterling getting barged over for a first half penalty claim, and having overstretched and already falling before contact for the one he did get in the second half, the most controversial thing was Sterling given offside for a ball that came off two Swansea players. 2 min 50 sec of the video:
https://oload.win/f/U08CSQ_2uA0/city_swa_2nd_half_eng.mp4
https://oload.win/f/U08CSQ_2uA0/city_swa_2nd_half_eng.mp4