Yes I was sitting out with her and she has also been expelling just a light yellow liquid. I heard back from our vet who I’d recommending we soak her in warm water and we can drop her off for an exam in the morning. Hopefully she does ok until thenThe poop indicates something is going on. It's not in the range of "normal".
My 6 girls are about 21 weeks and i was concerned about impacted crop as well. I came out to coop this AM and fortunately it has emptied, but i worry cause how much lower her crop hangs than the other girls. I read maybe hers empties slower. Either way, i will be having a crop bra made soon. There is a link on one of the threads here where the lovely person sews them for her lovely 12 yr old chicken! I took screen shots of her design. I will add the pic and maybe you can find the thread.It would be highly unusual for one so young to go broody. I've had many broodies and they don't look sleepy like your girl does. If you touch them they growl and puff themselves up, and some will peck you. If you take them off their nest to have a break they will sit for a few moments and then realise it's break time, then they will get very busy eating, drinking, dust bathing, then go back to sit on their nest once all their needs have been attended to.
I did have one first time broody recently that I thought was dead because she puts her head down on the bedding with her neck stretched right out, which is weird. The first time I saw her doing this I grabbed her to remove her from the nestbox thinking she was dead and she growled quietly at me, so I realised she was very much alive.
Hopefully someone will be along soon with some advice, as this is not my area of expertise. If her crop doesn't shrink overnight I'd be very concerned about it having slowed/become impacted.