I've had major anxiety attacks, and I've had the same anxious moments that you are referring to also. Believe me that a panic attack is something you will know if it ever hits you.
I had one panic moment when I brought my first child home and laid her in the crib for the first time. It went "OMG! I'm responsible for taking care of this baby!" and it passed quickly when I told myself that I'd know what to do.
It seems to me that the feelings you are having are related more to the effects of following a baby's schedule. What you mention seem to be related to concerns about time. What should I eat? The baby is asleep, so I better take advantage of the moment and fix myself something to eat, but what? I'm not really hungry, but if I don't eat now, who knows when I might get the chance next?
Another example: the baby's down for a nap now. I've got an hour or maybe two before he wakes up. Should I do laundry, take a nap, watch TV, or call my best friend for a chat? Once the baby wakes up, it's all about the baby and this is the only time I have to get anything done ... and then you end up "doing nothing" except trying to decide what to do.
I'm 25 years away from the last baby, but we care for our granddaughters including a 9 month old. When I read your message, I clearly remembered those days especially when I was on maternity leave. I would be heading back to work and I wanted to spend as much time with the baby as possible, but as I regained my energy from pregnancy and childbirth, I was also fretting about arranging child care and getting into some kind of schedule or routine with the baby.
At 4 weeks was pretty much the time my babies put themselves on a schedule so that I pretty much could predict when they'd wake and sleep and when they'd nurse. They liked their cuddle time and I loved cuddling them, but we both got content with alone time for the baby in her swing or crib so that I could take care of my needs like showering and using the toilet or folding a load of laundry.
With two kids, time management and balancing demands are even more complicated than they were with the first child. It becomes a good opportunity to introduce sharing, helping, and being patient to an older child.