I have been doing workouts at home for a while now-modified pike pushups, weighted pushups, weighted inverted rows under the table and pull ups, along with pistol squats. I read that one must "unshrug" shoulders (ie, bring shoulders down if you're standing up aka the opposite of shrugging) during pushups and other upper body exercises in order to minimize risk of shoulder injury. To stay on the safer side, I have been unshrugging as hard as I could, but the last week, I felt quite a bit of pain in the traps and upper back area close to the neck after doing weighted pushups that way (first time), and while the pain subsided quite a bit after two days, I tried doing normal un-weighted pushups a few days later and still got pain. Here's a pic of the location of the pain:

https://imgur.com/a/OtMpsnJ

I haven't worked out much in the last week for fear of aggravating that pain and just unshrugging my shoulders with moderate force causes pain in that region shown in the above pic.

Personally I think I overdid the "unshrugging" part but so far I haven't been able to find any advice specific to my situation on Youtube or any other place.

I'd really appreciate any advice for correcting my movements on the upper body exercises as well as any corrective exercises to help directly with the pain in that area.