A Good Song to Wake Up To

You're good at this. At this point, there are only a few suggestions that could help you take your music from good to great, because you seem to already have songwriting skill. Even the transitions are smooth, which in my opinion are the hardest parts to do.

Here are my suggestions:
First, invest in some higher quality instruments. The synths are fine. The drums could be replaced cheaply. Finding a low cost replacement for Slayer might be harder. Most importantly, buy FL Studio! I know it has nothing to do with your song's quality, but it will save you frustration in the future. When I started music, I had the demo version too, so I respect anyone who can put a song together with that.

Second, adding something high pitched during the parts where the bass synth and the drums play together would bring it out a bit more. I'm thinking a quiet atmospheric synth sweep, or some quiet bell runs up or down the octave. You could also add another percussion instrument there, or switch up the bass drum kick, maybe every other measure so it still has that driving dance feeling.

Finally, some EQ could give your song a unique sound that distinguishes it from other songs made with FL instruments. Reverb on the drums to match the synths would be good. But that's all mastering, which you said you haven't done yet. Overall, this is a good song. It's catchy, even without the mastering. I looped it while writing this review, and after listening to it that many times, it has grown on me even more.