Practicing Adverb & Adjective "Subordinate clauses and Punctuation marks"

While I was taking my an online writing course at home, the doorbell rang many times.  But I couldn’t hear even one ring.  Shortly after, my noisy cell phone started to ring.   I said to myself, “What the hell is going on.” I should have made my phone silent to focus on what I was doing.  Anyway, I took off my headphones to see who was calling me at such an early time. It was about 3:00 am.

You might wonder why I was taking a course at such an early time! Don’t worry! I’ll tell you.
The course that I was taking was offered by an American online learning center.  And the planned time for the sessions was set to be held at 9:00 pm, the American time. Due to time zone differences, as Egypt is 6 hours ahead, I had to take the course at 3:00 am.
Anyway, let’s go back to our topic.

When I picked up the phone and looked at the phone’s display, I was shocked! It was my old friend Salah for whom I was supposed to be waiting for him at the train station at that moment.