Anxiety Support Group
Anxiety is a physical condition marked by intense and persistent feelings of distress, fear, angst or dread. General anxiety caused by routine day-to-day stresses usually passes quickly and is experienced by almost everyone at one time or another. However, such feelings that linger over time and are very difficult to cope with, and which lack a clear cause, may indicate...

Separate your sentences in your journal as well.
You're taking the important first step in writing it out.
What life do you want back? Write it out and look for the clues in the words of the songs.
Fast forward to the 70's and my psychotherapists were working with me to use music therapy for channeling and reframing repressed emotions, reframing, etc. I still use those therapy techniques, even though, at present, "Music Therapy" refers to the spectator sport of listening to music. I still haven't unlocked the mysteries of that evolution, but am at peace with allowing different strokes for different folks while looking for new names for my old world "Music Therapy."
Anyhoo. . . All that verbal vomit is a lead in to restating my encouragement to get those songs out of your head and into the real world. Learn the songs on a musical instrument. Don't forget that the voice is a musical instrument and singing is a breathing exercise.
Whether that encouragement works for you or not, thanks for the update. Keep venting. Your own, strictly personal answers are in there.
Gentle support while you sort. Listening. . .
Writing thoughts in my journal helps to improve my mood. I hope it will work for you too. Try to do things that you will enjoy, it might help you from not being focused on the song that you heard. If you think you need more help, try to have a visit with your therapists. God bless you with His peace. Please keep us posted.
Also, please check with your doctor before starting or stopping any medications.
Self medicating can be tricky. Zzzquil contains an antihistamine. Similar to taking a Benadryl, or an allergy/cold medicine. What concerns me is the liquid Zzzquil also contains 10% alcohol.
Call your doctor. Let them know what is going on. I am sure they can help you with all of this. Don't give up. There is help out there.