You booked your parent's appointments on time. You moved your own. That is the pattern, and it is so common among daughters who care full time that it almost looks like a rule. You are allowed to book yours first, and you are allowed to stop treating your own appointments as the thing you will get to after everyone else is settled.
Local option: New Plan Care gives families in the St. Louis area in-home help so a parent can stay home: companionship, help with bathing and dressing, meals, and overnight care. Call (314) 405-0887.
What slips first
The appointments that drop off are the ones nobody else is waiting for. Your parent's ride has a driver and a date. Your dentist recall, your eye exam, the follow-up your own doctor asked you to schedule, and the prescription of your own that you keep meaning to pick up have no one chasing them. They sit in a list in your head, and the list gets longer each week.
How to tell it has started
Check these honestly. You cannot name the last time you saw your own doctor. A standing appointment of yours has been rescheduled more than once. You have been saying after this week for more than a month. Something you noticed about your own body is still sitting on your list with no visit attached to it. Any one of these is worth acting on. Together, they mean the gap has already opened.
What to check on paper
Write down each of your own providers, the date of your last visit with each, and anything they asked you to do that you have not done. Then pick the one you can book this week. Count what the visit actually costs in coverage: the trip there, the waiting room, the drive back, and the hours your parent needs someone in the house. Compare two ways to cover that time. One is a short block with a helper you already have, including a backup helper if your usual one is not available. The other is a visit that can be done by phone or video, if your own clinic offers that for what you need. Ask the clinic which one they accept for your situation, rather than assuming.
What to say when you book
Ask the scheduler for the first opening that fits the coverage you have, or the last slot of the day if that is when your helper can stay. If the office has a form or a note field for caregivers, use it, and ask what they need from you. Bring your written list to the visit. Ask your own doctor which of the things you have noticed should be looked at first, and whether anything on your list needs a follow-up date before the next visit.
You are not failing your parent by taking your own appointment. The one that keeps getting moved is the one to write down first.
If the trip itself is what blocks you, the programs on the local help page are a place to start asking about respite hours, and the Start Here page lays out the order to ask in.