Don't feel guilty, it's the way chess works. Challenge to another game to make up for it, that's what I offer. Or, if you know you are lower than you should be, just work on playing up until you find your spot, there's no other way to manually increase your rating. Just keep playing.
Unintentional sandbagging

I'm playing only my second daily 960 game so my rating is only at 391 but my rapid is 1160. The person I'm playing is rated 1047 in 960 but I sacked his queen early and have a 13 point lead only 9 moves in and I'm feeling a little guilty. I thought there might be a way to manually adjust your rating but I don't really know how that works.
Wait. How did you...sacrifice his queen?

Sacking the queen is akin to sacking the quarterback in American football... Pinned him so that the queen couldn't escape.
I'm playing only my second daily 960 game so my rating is only at 391 but my rapid is 1160. The person I'm playing is rated 1047 in 960 but I sacked his queen early and have a 13 point lead only 9 moves in and I'm feeling a little guilty. I thought there might be a way to manually adjust your rating but I don't really know how that works.