Feeling so guilty

Do you ever just lose your patience with your almost 4 year old? I’m alone some nights to put my 2 kids to bed. My husband works late sometimes. Tonight I was just so mentally exhausted. My son just wouldn’t go to sleep, kept asking for his dad, kept wanting to lay with me and touch me and tap on my arms lol and start knocking on the walls. Anyways, I just felt bad because he knew I was just livid & losing my patience. I’m scared things I do & say on days like this will really affect him in the long run. I’m so so scared. But I don’t even mean to be so mean. I just forget to breath and I start being impatient & so ugly mean with him. I’m so scared he hates me now. He even asked me not to be mad and just still was being mean with him. I’m such a failure. I feel so bad. I don’t deserve to be his mom. I just wanted to be left alone before I had to go to bed. My 2 year old fell asleep at 7:30, but my son was having a hard time falling asleep and he missed his dad. But I just wanted some alone time. I shouldn’t feel this way though since he will be grown one day. What’s wrong with me 😞