Yeah, definitely too big but per their size chart and in the "true" size style so it's not too ridiculous. I'll just look like a teenage parkrat (from a distance anyway).
The outwear you bought is solid. Sizing can be personal preferance but I'm thinking you may have gone a bit too large. Sessions gear fits long and baggy as it is. At 5'9 170lbs I wore a medium Sessions jackets and felt that was too large.