Basically the country is in a political stalemate, something that could never happen in the US because your political climate dictates that one of two parties has to win.
We're in a position were one party (Conservatives - also refered to as the Tories) has the biggest number of seats in the Parliament but doesnt have enough to hold complete power ie has only around 40% of the seats, it would need over 50% to form a strong government. The opposition parties (Labour, Liberal Democrats/Lib Dems, SNP, Plaid Cmyru) have the rest of the seats but this encompasses around four or five parties with the two larger ones not holding enough seats to have more than 50% even if they joined together (Labour, Lib Dems). One of these two parties (Labour) was the former ruling party as well, so if they joined into a coalition with any other parties to hold on to their rule then it would look weak because they lost out on the popular vote.
Meanwhile, the largest party only got 1 seat out of a possible 60 something in Scotland, which basically means that if they get into power then the election result is exactly the opposite of what nearly all the Scottish people voted for, ie the UK parliament leaders would been decided by English folks alone.
Add a botched voting system into this and you have a recipe for disaster.