about plagiarism

hi guys
im year 2 computer engineer in soem uni in london and we had an assignment/coursework set like a month ago and it was about programmnig using microsoft visual studio.. the programmnig was about building something / some 2d or 3d shaped or whatever) and inserting equations and making calculations such as area volume of triangle or whatever..
its %85 of the module and the rest %15 was a class test.
i was in library editing and adding some last things to my programme, then i went away for 10 minute leaving my computer logged in and my friend was having issues next to me to write the programming and when i came back from smoking i saw he pretty much copied what i did and then we both submitted our work.. then i had a look at his coding and mine and i can say like i got 400 lines of codes and he has like 260 but some of his lines are exactly same as mine like copy pasted and most of the time when i was declaring functions like float area( x1, x2, x3, int d) what he did was x1, y1,z1, int &c ) and mainly similarities like this in the whole code.. we got some exactly same things but he mostly made up stuff making very similar to mine as i just showed.. anyways i didnt react at all that moment but then suddenly when i came back home i started to panic and worry and stress a lot that if they would catch us because it says they are going to be using specialised software to check for any unfair practice corodnator.. I mean all parties involved would get penalized but iit wasnt my fault .. i mean is it possible for us to get caught if they run the specialized software? or we will be fine bcuz the codes are not exactly same but very similar in some places.
like what exactly does the software analyse? y'all know what i mean hopefully.. please answer guys im so worried