It does look like swelling, but could be weight. Is it sudden onset swelling?
My chams eyes are a little less puffy, more of a pronounced “lump”… which ive always suspected was debris or keratin buildup. The swelling in the corner could be infection, keratin, debris, blockage, etc. I would contact your vet. Mine gave me a course of antibiotics, both oral and eye drops. Infection could be secondary due to scratching the eye (Ive done that personally, and it was painful for me).