SORE= /sɔ:*/ Hurt, in pain. This first line compares physical and emotional pain by mentioning soreness, a lingering effect. Shawn Mendes describes how at this point in his life, he has been hurt more than he has ever been hurt in the past.

DEEPER= (comparative of DEEP) Deep is profound, well inside. Her words, like knives, stab him.

BREATHE ME BACK TO LIFE= He is just heartbroken and he is looking for someone else to bring him back up and love him.

GOT A= (I've) got a, I have a... Got a feeling= I think, I have this intuition about it..

GOING UNDER= If you go under, you are mentally destroyed.

I'LL MAKE IT OUT (ALIVE)= I will survive, I'll get through this. The complete sentence is: I know I'll make it out alive if I quit calling you 'my lover' and move on.

QUIT (+ -ing)= Stop.

MOVE ON= If you move on, you leave a painful past behind and start a new life.

BLEED= To lose blood (for example, if they shoot you, you bleed, your red liquid, blood comes out of your body)

ONTO (expressing movement)= On.

WITHOUT YOUR= Here we can see a very common assimilation which is T+Y= CH, so he pronounces /wɪðaʊtʃɔ:/.

STITCHES= When you have a serious cut, you need stitches to help your skin repair (see picture)

TRIPPING OVER= If you trip over, your foot hits something and you almost fall down. If you trip over yourself, you are so weak that you can't walk properly and one foot hits against another foot and you almost fall down.

ACHING= /eɪkɪŋ/ Hurting, feeling pain, suffering.

BEGGING= Asking in earnest (saying: please, please, please...)

TO COME HELP= To come and help, to come to help (me).

MOTH= One of several species of butterflies that live by night or inside your wardrobe.

DRAWN TO= Attracted to.

LURED= If you lure somebody to a place, you attract them to that place using a strong kind of attraction or persuation or trickery, almost irresistible.

SENSE= Feel.

BITTER= Sour, like the taste of vinegar. When we talk about feelings, "bitter" means more or less "very bad". The expression he uses, "your bitter heart", means that her heart is making him suffer.

COLD TO THE TOUCH= (your heart) is cold when I touch it.

GONNA= Going to.

REAP WHAT I SOW (AmE /soʊ/ BrE/səʊ/)= If you plant something (for example rice or corn), first you have to sow it (put the little seeds inside the earth) and then, when it grows and is good enough, you reap it. The expression "you reap what you sow" means that your present situation, good or bad, is the consequence of your past actions.

I'M LEFT SEEING RED ON MY OWN (heart)= Now, the consequence of what I did is that my own heart is red with blood (not the normal blood you expect inside a heart, but the kind of blood you get when you physically hurt somebody, for example with a knife). This is a very strong metaphor of deep suffering: my heart is bleeding.

NEEDLE (see picture) AND THE THREAD (see picture) are the two things you need to stitch a wound.

GOTTA = (coll.) (I) have to, I must...

GET YOU OUT OF MY HEAD= Forget you.

WIND UP= End up, finish (in a specific situation)