I know exactly how you feel, it's horrible at the time but it does get better. TBH I found it easier not staying as that upset Charlie more, usually once you have left they settle down...she may have been playing up as you were there??'
Charlie started 2days a week at 9months & took what felt like a life time to settle in. They even said that there is hope for all other kids LOL we thought he would never settle. He now is in 3days a week, goes to the carer no probs & only cries every now & then. He doesn't cry anymore when I get there in the pm either which is nice. Though 3 or so months on he still does NOT sleep at daycare. The most he has is half hour & he is still a 2 day sleep baby at home. But they say he's happy so they just let him be. By the time i get him home witching hour is truly set in but he's in bed early so DH & I get some nice us time.
I hated leaving him there crying hysterically each time, but I also needed to work & just had to be strong to get it to work for both of us. I almost gave up, but he is fine now & we are all happy...it does happen it just takes time for some. Think a little tough love & they soon get the hang of it. Hope it goes well for you, it is hard at the start.