In order of age of first use:
Under 14
Caffeine
14
Alcohol
Cannabis
15
Tobacco
DXM
Psilocybin Mushrooms
Codeine
16
Salvia Divinorum
Ecstacy (non-MDMA contents)
Amphetamine
2C-I
Ketamine
17
Hash and BHO
Alprazolam
Cyclobenzaprine
Oxycodone
Morphine
Diphenhydramine
DOx (Sold as LSD)
18
Cocaine
MDMA
Clonazepam
LSD
Legal smoke mixes containing JWH-018/JWH-073/HU-210/CP-47,497
LSA
Butylone
Nitrous Oxide
Diablo XXX (contained stimulant and psychedelic piperazines)
Kratom
Zopiclone
Oxazepam
GHB (only via GBL)
Mephedrone
Methylone
19
Methylphenidate
Lorazepam
Temazepam
Diazepam
Phenazepam
MDPV
Buprenorphine
Hydromorphone
20
MDA
Flurazepam
I'm 21 in 18 days, so things have slowed down for me in terms of trying new drugs. I have no interest in any RCs or any stimulants or any psychedelics. The only drugs I would really like to add is Methoxetamine, some more opiates and some more benzos, but really am not too concerned either. I still use drugs quite regularly, just ones I've already done which I find I've enjoyed the most (or haven't caused me much harm, at least). Cannabis, Opiates, Benzos, Alcohol, Tobacco, Ketamine (very rarely), Mushrooms (very rarely), pharmaceutical stimulants for studying (very rarely).