Factors that break and don't break the fast

Swallowing the moisture on one's lips after wudhu while fasting

Q: The moisture left on my lips from washing my face/mouth during wudu, is this safe to be licked and ingested when fasting? Usually after I wiped my lips in wudu, I have to spit and then let my lips air dry and/or wipe with a tissue until dry. Today after wudu, the majority of my lips were dry but in the corner of my lips I felt a coolness, which may indicate that there is still moisture from wudu left. I licked that area. So now I’m just wondering if my fast is valid. 

Mistakenly drinking water while fasting

Q: A person forgetfully drinks water in Ramadan. While drinking water he suddenly remembers that he is fasting. He stops drinking water but while he was remembering that he is fasting he might have drank a little water. That means he drinks a little water remembering that he is fasting, but he did not have any intention to break the fast. He then continues the rest of the day fasting. Is his fasting valid?

Forgetfully eating while fasting

Q: I have started qadha fasting of my previous fasts which I did not make up in time. Today accidentally in morning I forgot that I am fasting and talking to my friend she offered me sweet and savoury and I tasted some of both. I did not even remember after sometime that I was fasting when during conversation I told her I am fasting nowadays and realised that I was fasting and have eaten by mistake. I know in Ramadan you can continue the fast but I don't know if it applies to qaza roza as well. Please tell me if my fast is valid or do I have to do anything else?