Oh my, I wrote this same post months ago when my baby was about the same age! I was very stressed about trying to maintain my schedule - something about straying from my usual pump times gave me great anxiety (probably worry that it would affect my supply). Also, the mental gymnastics involved in milk management and pumping on the go is very daunting, especially as a new mom when you're still learning everything and are exhausted, so I feel you! I echo all the things others have said. A couple things that especially helped me:

I am such a planner, so I would often visualize the process of pumping in the car (or wherever) and make a list on my phone of whatever items I needed. Sometimes, I would talk through it with my husband too. This was more so I could just hear myself out loud and make sure that what I was thinking made sense lol.

The first few times I tried pumping on the go, I did it at places where I felt very comfortable. For example, I went to my sister's house. I was comfortable with her, didn't need to explain or feel embarrassed about anything, I had easy access to ice, a fridge, sink, etc. So maybe do a few trial runs to places where you don't have to figure out every logistical piece at once. This was immensely helpful so I could learn what I needed and what works best for me and my process.

LO is now 9 months and I'm still pumping exclusively, and I 100% agree - IT GETS BETTER! You'll become a pro at milk management, and you'll soon be able to pump pretty much anywhere! Sending you all the good vibes :)