Hello Ahmad, thanks posting the query.
In yours case nothing is abnormal and fluid discharge during talking and walking with girl friend is just due to over excitement and that is not abnormal but a healthy sign that you are perfect.
As far as concerned about strong erection that is a dilemma in your mind and some quacks ( so called sexologist
) loot money from ignorant persons.
Still if you feel dejected pl take an anxiety
treatment and some anti depressant
at the advice of some psychiatrist
Remove all distorted things from your mind and enjoy life as you are healthy.