The terminology premature ejaculation is no longer used because it is a misnomer. It has been replaced by Early Orgasmic Response (EOR). EOR is not a disease or disorder but merely an issue of mistiming between two sexual partners. A male with EOR with one female partner may not have the same problem with another female.
Masturbation is a normal, natural, harmless activity and has absolutely no adverse effect. If recent research is any indication, it has beneficial effect in reducing the risk of prostate cancer in later life. Most unfortunately, quacks are misleading the younger generation to make money.
If there was no problem of mistiming in the past, some development (physical, psychological, emotional, inter-personal) may have taken place. Obesity itself and lack of physical activity leads to sexual disorders including erectile dysfunction. For a height of 167 cm, you are at least overweight by 20 kg. Over and above that you are taking gemfibrozil (Lopid) which can cause sexual dysfunction.
Clofranil (clomipramine) is an anti-depressant that will cause more problems instead of solving. Lignocaine is a topical anaesthetic. Its use in EOR is explained by its de-sensitising effect on the skin. If you are not using condoms, it can have adverse effect on your wife. I understand that Durex has come up with special condoms with lignocaine applied inside. You can try this. At least it will do no harm. Once your organic issues (obesity, drugs adverse effects) are resolved, you may need no further treatment. You can also use squeeze method to delay ejaculation and/or female-on-top method. It is well explained in a book by Masters and Johnson.