WHAT THE FUCK?

Marija
So,my ex bo called me reciently,and he was going trough some difficult stuff and needed someone to talk to,and I told him that I'll let him know when I can,he was free at night since he works from 3am till afternoon,and I sent him text and then called him,but his phone was constantly ocupatted.And I saw him the other day in the car passing by me,and I texted him on whatsapp :"so what?We aren't even gonna say "hi" to eachother anymore? " And he was like: " WTF? If you had ever gotten to know me you'd know that I would never ever do that to you,plus why didn't you say Hi to me,or texted me,we needed to go out remembar? "
And then I say to him that I didn't wanna do it since he had blocked my number,and I wanted to know why...
And he was like? Wtf?I haven't got any of your calls,and I'm in a hurry lately,so if you noticed I didn't respond to your text you should've call me...(wich I did...it always said it was taken)
And so we started an argument...I just told him I'm not in a mood for that and that I would like to see him,since I know he is going trough shitty stuff lately...
I don't know what to think...Is it possible that smthg went wrong with his phone? 
This is so strange of him..I always though that he was matture enough to say If he wouldn't like to talk to me...How come his phone had always said Occupied?