I entered the bathroom and closed the door behind me. Once undressed, I put on a bikini. I'd bought a bikini along with the swimsuit just in case. And I was right because I'd tried the swimsuit on first but it was way too small and didn't even go up my thighs and so I ended up wearing the bikini instead.
I was quite sexy in it but there was one problem, thought I'd entered it, it was tight. Very tight. The bottom of the bikini was tiny and I discovered only at home that it was a thong.