amandal , this suggestion may sound a bit 'out there' , but ...
in consideration of the fact that this canvas was 'hidden' ( @ least that's what I gather , from your postings ) behind a framed print , perhaps it may have been stolen ( or hidden for some other reason ).
Althought it seems as if it was done in the style of the artist , the skill level seems a bit 'off' for the artists' work , and of course may be a copied work , as other posters noted .... but who knows ?
The fact that you purchased the frame at a legit shop should be a very good 'CYA' , in the event that your painting was purloined , or the work of a forger .
I've also discovered several paintings on canvas 'hidden' behind others , 4 out of 5 of them were forgeries of famous -to - semi-famous artists .
Speaking from the viewpoint of an old-timer - the rule is - "If there is a doubt , there is no doubt ; check it out."
The F.B.I. has got a large database on stolen artworks and legitmate collectors will sometimes check with them about a work they've bought or are intending to buy .
An individual needs to get in touch with a field office of the F.B.I. , generally , to check artwork against their stolen art database though .... not everybody is comfortable doing so , however .
Just junk-food for thought .... I'm not saying one thing or the other here .
I 100% agree with the opinion of having it seen by someone in the know , as previous posters suggested .
One last suggestion is to handle this canvas with clean white cotton gloves ...acids from your hands can cause damage .
