A Complex Solution, ya cont. w/ paranor.& romance (Revised)

Cool October air sweeps inside as I pull the front door open. Bailey, my yellow lab, waits patiently as I shake my legs out and loosen my quads.

My grandmother steps into the foyer, the morning newspaper in her hand. “You two heading out?” (I moved the dialogue to the end because it sounded stilted without a dialogue tag this early in the story.)

“Yeah.”  I need to run, clear my head before I have to deal with another miserable day. (Give a particular reason for why it will be miserable. Foreshadow. If there really isn't much reason she's dreading the day, then this story will have the same feel of having your MC wake up in bed. It'll feel boring.)

Gram touches my sleeve and I wince, my bandage rubbing against the raw wound. “You seem to be doing better, Lexi.”<--Great foreshadowing. I would still hint at something in the previous paragraph though.

“Mm.”

“I’m always here to listen if you need someone to talk to,” Gram says. 

“I know.” 
    

“Okay, have a good run.” (I took out Gram's dialogue tag up above, but this chain of dialogue still needs an action to break it up. I would include an action from Gram here.)

I step outside and head to the bottom of the grassy hill. I want to talk to Gram. But I can't. I told her I was better and I need her to believe that. She can't know I'm cutting again.  She'd be so disappointed in me. But it’s the only way I can deal with the isolation at school. With the bully, Jess, who’s making my life hell. <--I edited this here because it was a comma splice.

As I’m ready to cross the street, the open mailbox door catches my eye. I jog over, peer inside and draw out an envelope. 
   

Lexi V. Thompson   

My pulse quickens. Who’d be writing to me, at this address? I’ve only lived here four months. My hand shakes as I turn the envelope over, but there’s no return address.

The lead pulls taut in my hand. “Hang on, Bailey.” I unseal the envelope and pull out a letter.

Great start to your story. Aside from the comments I provided, this looks like a strong runner for Query Kombat. Good luck!