I feel like a terrible mother.

So earlier today my baby fell asleep after I got done feeding him. He didn't nap for a while so I assumed he would take an hour long nap if not more. I placed a blanket on him and tucked him in since I can watch him. Well then, a few minutes into his nap my brother in law calls me outside to talk. I grabbed the baby monitor and put it in my pocket thinking I'll turn it on a few minutes after I go out.

Well I forget about it. We talked for 10 minutes and then it hit me. I didn't turn the baby monitor on. So I turn it on as fast as possible and I hear my baby shrieking. Not normal crying. Like in absolute terror. So I run as fast as possible to my room and I see the blanket I placed on him completely covering his entire head. I grab him and he's soo hot and red and is breathing fast and in distress and I just break down in tears. Ever since then I cannot stop crying. Even looking at my baby now makes me upset because I feel like he doesn't deserve me as a mom. I think what if I didn't remember to turn the monitor on at that moment and another 5 minutes went by? I'm a mess. I feel so terrible. I just needed to vent. It just really messed me up