This thing came out with sperm, what is it? [picture]

Hi, Little background: There was blood in my sperm couple of months ago, but as it only lasted for about a week or two and went away, I never went to doctor about it. Now last 2 days my left nut has felt tender and today when I masturbated, ejaculation was little painful, so I felt like checking if my sperm look alright or if there was blood etc. Well what come out with the sperm was couple of small things, sort of like a pouch of skin or something - you be the judge. Does anyone have any idea what this is? I have a feeling that it is related to the pain in my left testicle sack as now the tenderness is practically gone.

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