Congrats, you've entered the fascinating world of clay bustin'. Enjoy....
FYI, the ATA says the average first round is 13/25 clays.IOW, ya did OK.
Screw in your most open tube for Skeet, same or the next tighter one for SC. Have fun, and when a year or so from now when most everything you shoot at dies or busts, marvel at your progress.
Nobody gets proficient at shotgunning w/o burning up lots of shells. The clay games are the best approach these days, since shooting tons of real birds is frowned upon by the DNR.
And for those who doubt that trap has any real world value,try acquiring a FAST sight pic on a 4 inch disc moving at 35 MPH, busting same, then doing it again as in trap doubles, skeet doubles or the ubiquitous doubles in US style SC. Note the width of your brain, or your heart, is about 4".
Note also that my trap 870 and "Serious" 870s weigh and handle similarily, even tho the TB is about a foot longer.
Nuff said....