Curiosity is normal, but drugs are not normal for anyone caught up in a group that do drugs (even 4 or 5 times a month) Peer pressure is bound to be a big factor to make you feel you should try them? Some people have no boundaries and no qualms about encouraging others either. Drugs are a blanket No No No No from the authorities but you may still be tempted to try something? Don't
Cannabis is still regarded as 'soft' but the strength of the THC can be very powerful, and widely linked to schizophrenia and mental health problems later down the line. Cannabis is still illegal despite all the social pressure to do otherwise. You risk a criminal possession record being caught with it.
Some drugs can have a severe and devastating effect on you as a user, and are highly addictive, particularly synthetic drugs. Some 'party' drugs can kill you even as a first time user. Unregulated, illegal drugs can be extremely powerful or cut with substances that you know nothing about and won't know about until you are unconscious (or dead) Drugs like cocaine are highly addictive and whilst it can give you euphoria and make you feel amazing to do stupid risk taking acts. It can leave you incapacitated by exhaustion, with expensive addiction problems and a perforated nasal septum.
The biggest problem of drug use is addiction, wrecked health and death. Never ever ever ever ever try heroin at all - ever. If you think you can't even give up sugar you will only have yourself to blame if you ever to try heroin in any form. You will become addicted regardless of how good you think your will power is - and then you might as well throw any aspirations you ever had down the toilet. Then learn to live with abcesses, and blood clots and join the wasted zombie club in the back alleys .
There are so many health issues with all of the illegal drugs there are too many to list. Look at the website 'FRANK' for impartial advice.
Aside from the health problems if you are caught with any illegal Class drugs you are liable for arrest and conviction. You can kiss your degree studies goodbye, because some Uni's take a very dim view and terminate your course if they are aware of drug use. Secondly your criminal drug record DBS check will stop you getting a job in Government, Defence Services , NHS and many professional posts.
If you love getting a natural high and need excitement - do sports. Do skydiving, bungee jumping or any adrenaline sport that nearly kills you.
So NO its not normal even if it is 4 or 5 times a month.