Verbally accepted job offer with new salary, too late to renegotiate?

A few days ago I verablly accepted a new job position within my company along with a salary. Getting up in the excitment of just getting a new job I accepted without even raising the question on if the salary was negotiable (the interview made it seem like the offer was set in stone, still i shouldve asked). Would it look bad to go back and try to inquire about renogiating for a slightly higher salary?

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