I was massive at 30 weeks, and a woman expecting twins sympathised with me because I looked so uncomfortable. From the back you couldn't tell I was pregnant but from the side I had the turning circle of a double decker bus.
Not all bumps are neat and tiny. We've got a picture of me at 27 weeks and I look like I'm about to give birth any moment. I was huge.
I needed all the space I could get in car parks, so I can understand why the OP might need two spaces in a car park that has smaller than average spaces.
By 30 weeks I couldn't walk very far, standing up was painful just because I was so big, sitting down was painful because I was so big, I'd had one operation related to the pregnancy and was due another, my feet were so swollen that my shoes didn't fit, but that was okay because I couldn't reach my feet to put them on.
And I had a complication that meant I was hospitalised for two nights and one doctor came to see me solely to say that he'd read about what happened to me (quiet dramatic, painful and scary, almost meant I had an emergency c-section to save DS's life) but had never seen it in person because it was rare, so he'd been glad to have the opportunity to treat me while it was happening.
And I had raging indigestion for months so had to sleep sitting up.
Also, I nearly died during my second pregnancy, because of an infection that reached my placenta following an accident that resulted in us losing our baby.
So I disagree with people who say pregnancy isn't an illness. Pregnancy itself might not be an illness but it can make you feel very ill and even the most straightforward pregnancy has physical effects on people and many pregnancies have complications that leave people feeling absolutely awful.
I find it really sad that people expect a heavily pregnant woman to be exactly the same as a not pregnant woman, just a bit rounder. My own experience has certainly made me a lot more aware of how difficult some pregnancies are, and I'm quite happy now to make allowances for people because of their pregnancies.