Can anyone please help me with wieght lifting please.?!

Ah, you've hit what is known as a "plateau". The most likely explanation is that your body has simply become used to the work out and when that happens, it refuses to expend further energy on increasing muscle. The solution is simple: shock your body. You've been doing heavy weights, so now do the opposite: do a weight which is so light that you can pump out 20 reps. Do your 20 rep workout for several weeks then switch back to your old routine. Hopefully that'll get you out of your little rut.

Also, how long is your average weightlifting session? Try and keep it less than 1 and a half hours (some recommend even as short as 45 minutes). I used to do 4 hour monster work-outs, then the moment I switched to 1 and a half hour work outs I made MUCH better gains.

Good luck and have fun.

it may help to increase your weight for each set. you could do sets of 5 with 75 80 85. then switch it up and do set of 3 of 85 90 95 100. do you know your max? there's calculations you can use to figure out how to improve & what weights you should use.

More protein and work different mucles don't just rest one day then bench agian give your body at least 2-3 days rest on that set of muscles.