I'm still a newbie at orchids (1 year) & someone wiser will probably give you good advice, but I've had this happen when bringing a new Phal home.
It happens because of condition change.
When I buy a phal at a big box store & it's in bloom, I keep it in the house so I can keep an eye on it. If it's doing ok, I leave it as is, if it's shriveled, I repot & cut off spike, so it can re-energize.
I have a phal.(year old) that was starting to form buds (outside on patio) & once our weather warmed up, I turned on a box fan in the window over phal shelf... buds grew & dropped off...
Anyway, don't feel bad about failures, we all have them... just read the posts ... find what does best for you