I want to find out if writing in a very minimalistic and futuristic style works for me, but when I look at what I have written, I cannot tell if it works or not and if it is "my style".
How can I tell if that style is for me?
There are two things you can do if you want to evaluate whether a writing style fits you: get feedback and self-reflect.
Asking for critique is always a good idea.
It is off topic on this site, but there are many communities dedicated to critiquing. Here are some questions that ask about where to get critique. Personally, I use a number of critque groups on Facebook. Just type something like "writing critiques" or "beta readers" into the search on Facebook and see what comes up.
Finding the right community and good beta readers will take some time. It is something you have to build like you have to build everything else about writing. So don't be discouraged if your first experiences aren't what you were hoping for. Just keep looking.
A word of caution, though. If three or more beta readers agree, the problems they point out are probably there. If only one person finds fault with something, it might be a question of personal taste. So always get more than one critique.
While reader feedback is very helpful when it comes to finding out what part of your writing you need to work on, it cannot tell you if the cause for the mistakes might by that the style you are writing in may not be for you. To find that out, experiment and use introspection.
To find your own "voice", a good strategy is to try out different things and to observe not only how they work for you (that's getting feedback), but also how you feel about writing that way.
Do you enjoy writing in that style? Does it come easy or do you have to struggle? It's okay if you have some learning to do, but if you find writing in a certain style unnatural and against your own sense of language, then it is probably not what you want to pursue.
Also, ask yourself, if the result pleases and satisfies yourself. Is it a style you like to read? Are you proud of your achievement? Or don't you know how you feel about it and whether you like it or not? In the end, even if you write for money and an audience, you must at the most basic level write for yourself, or you will be unhappy with your career. So look into yourself and see if you like what you do.
I'm slightly struggling with the frequent switching between the abstract and the sensation reading that. There's nothing wrong with a succinct style like this, it just currently reads like some sentences were omitted.
"That boy's good." Taffy playfully giggled, pointing to the somewhat good-looking boy sitting up front. The room was blue. Serene. Calm.
At first we are reading an action sequence, Taffy giggling and pointing, then we get a list of situational descriptions of the room. Why are they in a paragraph together? How to do they relate to each other?
None of these would be what Selena was feeling.
None of what? If this was in a paragraph with the room description, then it would be clearly a reference to those adjectives, but at the moment it's not clear.
Something swirled round and round
We've left the punctuated style here and switched to much more descriptive narrative. Also, if you could tell us what the something is (even metaphorically), it would add more impact.
his burning gaze
Unless it's lasers, this isn't in sequence. Tell us what happened (he turned) and then her reaction (and his gaze burnt). And how did she see that if her eyes were closed? In this scene we seem to be embodying Selena, so tell us how she experiences it.
Wink wink wink
Winking implies a different social action than I think you mean here.
I'm rather confused by the angels paragraph. Unless they have previously been mentioned, I think they need rather more explanation than they get here; do you mean to introduce them as characters in the story, or are they metaphorical or figments of her imagination?
Consider the edit:
"That boy's good." Taffy playfully giggled, pointing to the boy sitting up front. Selena silently appreciated what she saw.
The boy turned, and his gaze burned her. A rush of noise swirled around in her head.
Selena looked away. Stared at the walls. The room was blue. Serene. Calm. Selena was not. Not at all. She closed her eyes.
Her inner angels echoed in her mind. "You're fucking engaged", they hissed, surprisingly real.
She allowed one eye to open, peeping at her torment.