Anyone have gone through a difficult phase with first child after giving birth to second?

Hi all!

I am 4 months pp with my second child and my first is just a littler over 3.5 months.

I've been feeling so bad lately because I have the guilt and frustration that it's not the same with my first child any more.. I hate to feel this way and even to admit it. Some days are better, some days are worse but generally it's like I have such a lower tolerance towards my first and often distracted even when we're spending some alone time together. She is so lovely, clever and people comment on how well she is behaved, but of course she is going through that "terrible three" phase (although an mild-medium level lol). She still randomly wakes up at night or very early morning, which adds on to us waking up from baby already. The stubbornness, picking on food that I've made (used to be a great eater), etc. which I know all the three years old do but still is hard. I feel terrible because I keep on having to discipline her (not physically), get exhausted emotionally and I often can't even genuinely react to the funny/silly things she does! When we play, the constant pretend-play is soooooo hard (I used to enjoy it before birth) and the constant need to talk and react is exhausting. I feel so horrible because she has been my EVERYTHING and couldn't even imagine loving any other child. Of course she still is my #1 in my heart but I can't help but feeling like everything has flipped upside down, because I am so irritated often and feeling sad about feeling this way. On the other hand, second baby is seemingly so much easier than my first so even the continuous 30 min naps or fussiness doesn't get to me as much. I am cuddling and kissing him all day and it's the best, most calming feeling in the world.

I love my daughter so much and want to continue to be a great mom to her. It just makes me so sad that it's not same as before anymore and to even think that I have all these negative feelings in our relationship.

Just hope this is a phase and better days will come..