In week 5 flower some male flowers

into week 5 of flower and in week 4 noticed some male flowers (balls) but v v few have picked them off and trimmed bottom of plant where they mainly where. So assume have a hermie, My friend told me to keep checking and ensure picked before open but my question is if one male flower pollinated one bud or one branch would that pollinate the whole plant or just that bud/branch?

They will probably grow back again this early in the game even if you cut them off. Are you sure you don't have a fully male plant?....does it actually have both white pistils and balls growing on it?
It takes a very tiny amount of male pollen to seed out your entire crop; not just a branch or 2. If your plant is hermied this early you either have a light leak or unstable genetics.

Yes mate definetly female buds are growing and white pistils, def no ligtht leak but staying out of room in dark periods from now on and would def not recommend a lumi green led headtorch that's what I'm putting it down too, some people saying green led to powerful. I'm keeping a close eye on it and hopefully itl be ok fingers crossed

It does not take much light at all to herm out your plants. If you have been flowering other plants in there before without incident then the seed you have could be unstable. It's gonna be next to impossible to avoid getting seeds; and any seeds you get will likely be unstable as well...be vigilant & good luck.

Cheers mate, going to go with cuttings next time and sod the seeds off, seeds where from royal queen but yes do agree with you on the light, best to stay out all together I think when lights are off