Mixed voice problems, would like advice? :)

[TheMoreYouKnow]

Hey, now I've been struggling with this for quite sometime, and I'm aware that this forum is no substitute for real one on one voice lessons. The problem is, in the financial state I'm in I cannot afford them. So here I am coming here for advice instead.

My struggle is, is for over two years now I've known about the mixed voice and have been trying to do it, I've liked the sound of being able to sing higher with no strain. And I've gotten to the point where I can transition smoothly between chest and head voice without any breaks. but only sometimes... Yes I said "only sometimes".. Some days, I can do a full siren from highest to lowest quite easily, others it feels like there's an octave gap in between (not really, I'm just being over exaggerated, but it's still pretty large). As well, I feel like my mix is stronger at night time then the day, but that makes sense to me since my voice is warmed up by then because of me singing all day.

Now on to the second main problem: the days where I can "mix", my mixed voice is still quite week.. Volume wise it sounds the same as if I were singing in Falsetto/Head voice, (whatever you kids call it these days). Now I'm hoping that power will come later, once I can actually practice often instead of just when my mixed voice is actually being cooperative.. I hope somebody could help me out. By the way, if it's at all important, I am a 16 year old guy.

Thank you very much!