The reflexive use of "myself" occurs when you have a transitive verb and the object is you. For example, "I hurt myself" "I confused myself" "I washed myself" "myself" can also be used to reinforce the fact that the subject is you. For example, "I can't do this myself" "I made it myself" "I myself saw how bad it was" #2 falls into the first category and is OK (except you forgot to capitalise "I").
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