Hi, you're really off to a great start!
The bass-end is a bit weak on some parts, and for a techno-rock/metal-something-kinda style, I think it'd work just fine. Maybe try EQ'ing your way out of seperating bass-line and kick-drum, they are clashing a bit.
Personally I would cut a bit off on the highs on the intro-guitar, since it's very monotone (not particularly a bad thing), it's just cutting right through my ears..
Also, rhythm guitar's could have a bit more high-mid if you want to bring them forth a bit.
Again you're off to a great start, and the overall mix is quite well made, especially for 'your first mix'.. and most of it is really about personal preferences from now on.
so
1) More seperation of instruments (a lot of stuff is happening just in front)
2) a more punchy bass may suit this genre on some parts
3) really catchy stuff in the middle and end, sounds great - just too much going on at the same time
I would probably knock that crash to the right a bit down, make the rhythm guitars more visible, and seperate the synth and the 'lead' guitar.
4) Do you plan on putting vocals on this? - If so, you might have to prioritize a few things.
5) An overall limiter or multiband compressor might do you justice if used correctly, heck compressing that kick drum for some attack might help .. as of right now, the bass is kicking it out of the way - Try noodling with that compresser or make room with an EQ
6) Again, you got some nice rhythm guitars going on throughout the mix, I'd love to hear them more clearly, if that's what you're going for - remember to high-pass/shelve them around 200hz to save precious energy for the bass and kickdrum.
I'm no expert by far, but you bumped twice, so I tried to give it my best
Anyway, nice job so far - take a break, get back to it in a few days with fresh ears, try listen to your favourite songs, see if they got something in particular you could apply to your song to make it better.
best of luck, Christian