Got 4 months sober in a few days but I don’t wanna stay sober, I miss drinking n smoking but that wasn’t my main issue. Shooting dope was n I miss it so much, what should I do?
Go to a meeting, do some service work, and talk to your sponsor. If you’re not in a daily program like NA, please find one asap. 4 months sober is amazing. I’m sure your life was lonely and miserable 4 months ago. You don’t want to go back to that. Sounds as if you are heading in that direction. You can turn around and walk back towards recovery. Go before it’s too late 

First of all, I want to commend you for making this post. That shows you want to get help and find answers. Join a group, try an online meeting, try to get into your own personalized therapy, reach out to people on here…anything but turning your back on your recovery. Often times we miss the feeling of altering our conscious and not having to feel our emotions. We miss not having to feel. If you are going through a hard time, please seek help from others. Your life depends on it.
So questions arise based on your post. First being if you did drink or smoke how long until that leads to shooting up? I ask because if that is what is at the end of the road I would always miss that turn off. The second is why do you want to drink or smoke? Is it to escape or because of the social aspect? There is ways to replace both that lead to a healthier life.
I would consider what was so great the initial feeling? Because the WD alone is enough to keep me from ever even thinking about going back. I am lucky where as I wanted out. It was a vicious cycle but I never shot it. If I were you I would seek support in person or via zoom whatever you have access to. But please think about how awful that feeling of needing it and no control to the point you're sick and debilitated. It obviously got to a bad place for you to want to stop and you have. As much as easing life's struggles with aids such as drinking and smoking may sound helpful but it's just another bandaid. One that leads to a slippery slope while you don't need any distractions or anything altering your path of sobriety. 4 months is amazing but because you're still craving your drug of choice I would stay away from anything that may alter your judgment while using it.
Don’t fall back into the trap. You miss the idea of smoking, drinking, and shooting, but in reality none of these things offer any benefits, it’s just an illusion. Don’t scratch that itch please, it’s gonna get worse if you do. Better get pumped about your newfound freedom, don’t throw it away. You got this 
I would say it could be a slippery slope. Alcohol is my main problem but when I was drunk I didn't mind trying other substances because my inhibitions were lowered. The fact you're asking shows that you're worried what might happen. I wish you well, friend.
My ex gf just got out of rehab. She was clean 6.5 years. Her relapse started with drinking and ended up with speedballs. If your an addict your an addict. Escaping your feelings with a drink or a bong hit starts the spiral of craving.