Have I committed a sin by leaving the first congregation, and what is the ruling on my repeated prayer under these mentioned circumstances? And have I committed the sin of letting the prayer time elapse? And will Allah accept my make-up prayer, or will it not be accepted from me even if I pray it a thousand times, because I delayed it without an excuse?

Your first prayer is valid, and you are not required to repeat it. There is no need to consider the validity of your second prayer, and there is no sin upon you for praying on time. You did not commit a sin by missing the first congregation because those who deem congregational prayer obligatory do not make it obligatory with the first congregation; rather, they consider that merely more virtuous. You must be wary of yielding to obsessive thoughts.