Danny Welbeck probably was clipped by the Montenegro defender. He probably should have had a penalty.
The mistake he made was in going down like a second-rate actor, arms away from his body, flailing at the empty air. It's the same mistake that got Gareth Bale booked for simulation more than once this season. It makes even a genuine case look like a con. It's got "is he watching?" written all over it.
If you trip over in the street your hands shoot out in front of you to try to break your fall. They don't imitate a dying swan.