dude, i'm 72kg, and around same height as dark. for your weight, you are pretty darn strong! i only maxed 28kg dumbbells flat bench press for about 6 reps or so and i thought that was an achievement for me. anyway, being a bodybuilder is, i quote: "not how much u can lift, but how much you look like you can lift". some people have massive chests but lift relatively light weights for 10-15 reps for most of their bodybuilding journey. this is because there are 2 types of hypertrophy: sarcoplasmic and myofibular; in other words, one is emphasized more on size, the other on strength. but of course when u emphasize on size you will gain strength as well and vice versa.

anyway, don't be demotivated! bodybuilding (and any other strength programmes) is 80-90% diet. training is the easy part (since it takes only 1-2 hours per day, 3-4 times a week) but you have to watch what you put in your mouth throughout your whole journey! do some research on nutrition, focus more on your diet and i'm sure you'll break plateaus and make massive gains in no time 

good luck!