Should I talk to him?

so my boyfriend and I broke up this past saturday. i guess part of it was my fault. things havent been going well with us. we cudnt see each other and our relationship was just fading. on friday, the day before we broke up, i was busy and didnt get home until 11 and i found out he did not try to contact me at all for the whole day so i chatted him and asked him why but he did not reply at all. saturday morning i broke up with him bc he still didnt reply. however in the afternoon he replied saying he was sorry and that **** happened yesterday so he cudnt talk to me.i asked him how he was and what we are gonna do and he decided that we shud break up bc of school and how he is really bad with commitment and responsibility. but hed like it if we stay being friends. sunday was supposed to be our 5 month but since we broke up we didnt talk all day. now its monday should i just start a friendly convo? all i want is to just talk as friends. i miss him but i dont know if he does. i know he wud chat me back if i message him but i feel like he doesnt care about me anymore. he was very loving in the beginning and after the honeymoon phase i was always working hard to try and get the spark back but he doesnt feel it a lot of times and is cold sometimes. btw im 15 and hes 16. thanks in advance :)