Calvin's Commentary of John 20 says...
It is, unquestionably, an invaluable blessing, that believers can safely and firmly believe, that He who is the God of Christ is their God, and that He who is the Father of Christ is their Father. Nor have we any reason to fear that this confidence will be charged with rashness, since it is founded on Christ, or that it will be proud boasting, since Christ himself has dictated it to us with his own mouth. Christ calls Him his God, in so far as, by taking upon him the form of a servant, he humbled himself, (Philippians 2:7.)
This is, therefore, peculiar to his human nature, but is applied to his whole person, on account of the unity, because he is both God and Man.
The verse in question is...
"Jesus saith unto her, Touch me not; for I am not yet ascended to my Father: but go to my brethren, and say unto them, I ascend unto my Father, and your Father; and to my God, and your God." John 20:17
Even though this is Calvin's commentary, I'm assuming this is true for all trinitarians.
Since god the son was ascending to his god, and his god is the same as the disciples' god, and the god of the disciples is god the son, is god the son the god of god the son?