Aster?

I don’t remember planting this, and guess that it’s a plant someone gave me last year, during much of which I had brain fog, but it’s huge and colourful amongst the other plants that are slowly dying back. 

I’ve no idea what the man doing the ultrasound did to my knee, it didn’t hurt at all while he did it, but it’s been agony all day, and I’ve spent a lot of time feeling sorry for myself, as it had seemed to be getting better.