For my 2cents of information. I have checked my first go to sight Stamp Forgeries of the World (
https://stampforgeries.com/). They don't list any known (to them) forgeries for this stamp. My next site Stamps of the world (
http://catalogue.klaseboer.com/vol2...itavice2.htm ) does have a good quality photo of this stamp with the broken line. They also state that in type I, the line below the word 'QUINDICI' is close at the 'Q'. In type II, there is a break just below the 'Q'. Type I was issued on 10 February 1863. Type II was issued in April 1863. Both types were printed in sheets of 50.
I agree with you and spain_1850 that this definitely looks faked. Normally forgeries like this are well known and the stamp community works very diligently to inform everyone about it. The question remains is it or is it not a fake? I have collected many fakes over the years. I have a faked British Guyana (world's rarest stamp). US Confederates, Brazilian, and many others. All of which are well documented. The websites above do not show a stamp with the first printing. Which makes deciding if yours is real or not that much harder. I don't personally have either of them, so I am of no help on that front. If one of our members does have them, I would cordially ask that they please post them to this thread so we may investigate this further.
Your first stamp is well used and creased and distorted (probably water type damage) in places. All of which can cause it to look very different than the one on the right. The right stamp is pristine and very well detailed. Inks of this time ran/bleed often and easily. I would very much like to see a good quality photo of the first printing. I'll be waiting to see if any of our members can assist with this.