When a girl accepts to go on two dates with you, kisses you, shows major IOI's and then when you ask for the third date, she starts saying "Maybe, I have not decided what I am going to do that day." and then stops saying it and accepts to meet you after you ignored her "maybe"s and acted like she accepted it already...

Does this show that the girl is losing interest or playing her game on you?

Sounds like shes playing games. It could be getting serious and shes just shittesting you. I would just play it cool.

I acted like she did not say maybe and said "You will be having me next to you. What could be more interesting than that?" and she started laughing. Then she accepts it.

Do you think it was a bit pushover?

stop doin big things such as a "date" have her do little things with you so she will invest more time with you such as have her run erronds with you use the words "tag along with me" invite her to "tag along with you and your friends"... try getting a hooka while she is on a little errond with you ask her if she has smoked hooka before most girls have and like it, if she hasnt neg her for not doing it if she "says smoking is bad for you" then tell her hooka has no tar or anything that is bad for you because it doesnt, then neg again and she will most likely come with you... if you can play guitar that is good you can play while yall are smokin hooka... if you like to workout invite her to "tag along with you" to go workout basically the things you like to do invite her "tag along" with you to do it... dont plan a big event such as a date where most likely she have to be attracted to you to go on then she will invest more time with you and if she rejects you the first time dont react to the rejection say something like "no worries" or "no problem" because i high value male doesnt react because he has another girl he can go to so wait a week or so then invite her to do some little thing again....

I appreciate your advice but it looks like it has nothing related to my question.

There's no way to know what's going on in her head. She might not be sure if she's interested yet or might be interested but playing games. I think if she was completely uninterested, she'd just pretend she was busy that day and say no. She could actually have possible plans that day and is deciding between you and some other thing she planned on doing or person she planned on seeing. K I'll stop rambling- my point is you don't know what's going on so you should just assume she is interested. If I'm unsure, I always just assume interest.