Friends in Germany

Hello guys, I a(23M) just wanted to get this off my chest. I've recently moved to Germany in order to study a Master's degree here.My German Language is at A2~B1. I've been here for a month and I've been struggling to make even 1 friend! So, at first there was a Karoake in a Bar nearby and I said to myself, why not attend and try to get to know people there, or even try to sing a song? So when I went there i got to know two dudes, which were nice and funny we drank a couple of drinks and chatted about lots of things. Then we also sang 2 songs together. The guys really told me nearly everything about what they do and their life. I felt that we could be good friends or smth. At the end of the night I took both their numbers and texted them so that they send me the pictures we took at the bar and also get to be friends. It's been 2 weeks and they both won't answer lol. Also, I've met a girl at a dancing club and we got along really well, we chatted about alot of things and it turns out we have alot in common, at the end of the night she asked if we could exchange numbers and I agreed, the next day I tried to text her and she would be so late to reply or never replies at all, I feel confused honestly. Are all Germans like that? Why is it so hard to make friends here?