Good lord, man - a few things:
1. Why are dudes on this site always acting like they don't want a woman they can actually CARE for and show affection to?? It's okay to admit you want to do more than just screw her brains out - if you want to cuddle/hug up with/have her sleep overnight, that's not only fine, it's GREAT! It makes you a MAN to actually WANT a woman in your life as more than just an FB, and it's actually quite pathetic to act like you don't when you do.
2. You're over-reacting to the situation for NO reason other than your own insecurities. "Oh, she screwed me on the first night, so it's a red flag" - um, how about the fact that YOU also screwed HER on that first date? By your logic, she should be looking for red flags on YOU as well. How about you take it from a different perspective - that you finally got so good at knowing how "the game" works that you made her comfortable enough to WANT to sleep with you??
3. We say this on the site time and time again: if a woman flakes on you, it's a red flag... UNLESS SHE OFFERS A COUNTER-OFFER. Here you are boo-hooing about her saying she needs to help her daughter, and you're not looking at the fact that she basically said "Hey, Saturday's no good, how about Tuesday?" Like, she GAVE YOU A COUNTER-OFFER because she actually WANTS to see you still. Could she have been lying? Sure! But she also could have been telling the truth because things DO come up in life that make us have to change our plans. But again - SHE MADE A FRIGGIN' COUNTER-OFFER.
4. And btw, STOP THINKING IT'S NOT "ALPHA" TO ACCEPT A COUNTER-OFFER. I get so tired of guys on this site being like "Well, she's trying to change plans/dates/times and I don't wanna appear like a weak-beta, so I'm going to tell her NO!" Great - so instead of being understanding of the situation, you decide to whine to her about how you're not going to let her change plans to Tuesday... which makes you sound like you're throwing a tantrum, thus looking BETA after all.
5. Lastly, STOP BEING SO DAMN PREDICTABLE WITH THE DATES. There's no reason that EVERY Saturday needs to be already carved out for a date - why not switch it up and do it on another day, like... oh, I dunno, a TUESDAY or something?? In reality, she may have just wanted to be able to see you on a different day of the week - regardless, you should be doing this anyway!
In short: stop being afraid of having "feelings" for this chick; stop mis-reading these so-called "red flags" which aren't even there at the moment; and stop being so afraid of not appearing "Alpha" that you "Beta" yourself out of this situation. Hope this helps!