Talk to Andrologist on Erection Problems

AOA, I'm 25 years old. i recently got married but there's a problem that during intercourse, when i get discharge for the 1st time, its too soon and as soon as i get discharge i no longer be able to maintain erection even if i want and, for the next, i've to wait for 20-30 minutes. Plus as soon as i get discharged, a phase of coughs begins. Before marriage, i was too much into these things from very early age, plus i'm a chain smoker too since 2015. Please help me out or tell me if it's normal or happens with everyone? Is there any test to check out any kind of abnormality or should i consult doctor physically?