I think my baby ate a cigarette

So today hubby has been sleeping ALL DAY damn near. & the one little break I try to get (cooking dinner) he left his pack of cigarettes on the floor. The ONE time I think its okay to turn my back this shit happens!!! I see my 1 yr old walking down the hall hiding his hand. I walk up to him & he takes off running (I know by that he has something he knows he isn’t supposed to have) I see a cigarette butt in his hand. Just the butt. I started freaking out. I smell his breath & check his mouth & there wasn’t anything nor did it smell like a cigarette. I feel like the worst parent in the world. I do EVERYTHING around here to make sure its baby proofed. I know I’m not supposed to turn my back not even for a second. 🤦🏽‍♀️ I called poison control & they told me what to look out for but I’m pissed!! I found some of the cigarette but it’s still missing about half of it I’m guessing. The pieces I did find didn’t look wet or anything like they had been in his mouth. I’m still freaked out & cant stop watching him while he sleeps 😭