Instagram commenting?

[Carlos]

Okay so this morning i texted my girlfriend good morning, and she replied with "you know what dont talk to me. im done". so i flipped out, she saw a sieries of comments to a bunch of random girls on instagram saying "kik me sexy" or "your hot kik me" from my account. i didnt do that though i hadnt even been on instagram that morning but it says i commented this morning. but i didnt! I recently signed up for gramhoot to get more followers. can they comment? i dont even know these girls, nor did i comment those things. please help! is there any explanation? how did instagram do this

[Crystal]

Idk