IF I understand correctly you got the flashing under the shingle but added a adhesive cover piece to hide the job. If this is correct and you actually did get the flashing under a shingle I wouldn't have bothered with the cover flashing. What the cover flashing has the potential to do is trap moisture and freeze in between and create a dam. All that said you may be ok. Just keep an eye on it. If you have any of the adhesive flashing left I'd cut a strip and just slip it under the upper shingle. That may fix it for good and you won' have to worry about doing anything else. All in all it looks good and better than some pics folks have posted of "pro" jobs.
Yes, you understood me correctly but I will add that I added the adhesive flashing also to try to get a tighter connection all around to the composite roofing.
In your earlier post you suggested sliding a piece of flashing under that top shingle to overlap the cone flashing, I do like that idea. That flashing could be big enough to even go over my adhesive flashing with the bottom end all the way down to the cone flashing
Wow, I think I'm having a flashing back!
But seriously, when I take that storm collar off to clean it up I'll have a better look at the cutout I made in the cone and see if I can help that area. It was getting pretty dark by the time I installed that and the storm collar. And I hope by adding sealant under that top shingle I didn't create a problem for the future. Now I won't be able to go under that shingle, I'll have to go up a row. I'll just be flashing it to death!
Good suggestion so thanks,
Bryan