i bought my sir betta a lady betta and he's being mean

ok so i went to petco last nihgt to buy my sir betta, tapatio a girlfriend
becaus ei thought he was depressed and needed some lovin. at first when i put
her in there with him he was being flirty and gentkleman like but then he
satrted nipping at her and i dont understand becaus ei separated them and now
he keeps staring at her, his fins ares tiff like whne he gets mad but i dont
know if hes mad or excited. should i try and put them together again? i put
the lady betta(her name is WOW) with 2 little goldfish and they werent
fighting but she kept eyeing out one of them. i also went on a rampage and
bought 6 goldfish. i have 4 niow because my neighbor put the 2 big ones with
his fishies since he has a bigger tank. how long will my betta girl survive
if she doesnt have a filter? the thing is, i dont have money at all right now
to buy the goldies a fliter or a bigger tank and im not sure if i should try
putting tapatio and WOW together again any suggestions? =/ i really love lall
my fishies an di dont want them to die