You are normal. Don't worry about these things. If you are going on thinking the same it may end in erectile disorder.
You are able to do have sex without the help of pills, almost weekly thrice is quite normal for your age.
There is nothing to worry about the penis thinner at the base and thicker at the terminal portion which is also normal. Your erection would be rock solid during the age of you teens and early twenties and also for 1-2 years of marriage, After that it will be slowly decline due to age, amount of stimulation, refractility of your genital organ etc. If you have along gap of abstinence after which you will get good erection due to excessive stimulation.
There are many other ways to satisfy your wife by foreplay etc. There are new drugs available in the market which can increase the duration of ejaculation. If you practice Kegel exercise will also enhance your performance. If you approach any Andrologist or sexologist
they will guide you in these regards of drugs, Kegel exercise and the other ways to satisfy a woman.
You need hormone substitution.