Dear passion, what generally people think that anything coming from penis other than urine is precious thing and not to get wasted, totally wrong assumption , the sticky liquid is nothing but a secretion as a result of you mentally get excited ,is normal thing. in younger age group it is very common as they get excited many times with thoughts , visuals etc. hence when they strain or urinate the sticky liquid comes out.
2- During masturbation
people want to get pleasure as early as possible so they rush to it hence ejaculate with semi erection, not a big deal.
3- only 2 inch penile size after erection is sufficient for normal satisfactory sexual life but i doubt how you measured. if so is the case you are not going to face any problem as far as size is concerned.