The speaker describes being young and queer as two things at the same time: romantic and upsetting. Neither feeling cancels the other out. The poem is built around that tension, and it says the struggle is one "only I can understand," which makes it feel private and a little lonely.
The first half is warm. Being queer feels special and unique, and the image of "a rare gemstone in a ring" makes the speaker's identity something valuable and beautiful. Then the tone shifts. The same identity has to be "kept hidden" for protection, so the gem becomes something locked away. The repeated phrase "young and queer" stays the same, but its feeling changes.
The ending is the most striking part. "It is strange being young and queer" gets cut down to "It is strange being." The words trail off, as if the speaker's sense of self and the simple fact of existing have blurred together. The mood is quiet, honest, and unsettled.