Would anyone want to fake having a medical diagnosis for tendonitis?

I fell back in 2018 in my storage unit ; due to having to try to save my mom's guitar from being broken. Since my roommate had started throwing stuff out because he couldn't find what he needed at the apartment. When I quickly tried grabbing the guitar case , I slipped on a paper book which is when I fell down out my left elbow and left shoulder which now my roommate would be yelling at me saying I'm fucking faking this tendonitis which, he that tells me that his own girlfriend (8 years ) and own mother ( retired nurse for 38 + years ) who both are nurses in the ICU at hospitals. I got medical professionals that work on professional athletes like Chicago. When I got multiple MRI and all my medical doctors that questioned them, how would someone want to fake any pain? And all asked what you mean. they all me No on the faking any of this.
Would anyone want to fake having a medical diagnosis for tendonitis?
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