Welcome to e health forum.
The penis should always be measured always in the complete erect position, and not in the flaccid state.
With regard to the size of the penis, I would like to let you know that unless you are in possession of a micropenis - a rare condition in which a man’s erect penis is shorter than 2 inches in length - size does not and should not matter.
When measuring the penis dimensions, you need to consider the following :
1. length (the measurement from the base of a man’s penis to the tip) and
2. girth (the distance around a penis, usually measured at the middle of a man’s penile shaft).
The average penis ranges between 3.5 and 6.2 inches in length and between 3.7 and 5.1 inches in girth when erect.
In case, you still do think that your penis is very small, then consulting a urologist for a proper evaluation and discussion of surgical elongation of penis can be considered.
I hope this helps.