I don't think I've ever seen anyone post about that. This happens to me. When using heroin my lungs seem to get congested and during WD and/or days switching back to sub I'm frequently spitting out mucus. I end up swallowing some during the crappy sleep I get. My stomach is sensitive and has bothered me since I was a kid, so swallowing this mucus makes me feel really nauseated and I end up throwing up bile a number of times. The stomach pain is really brutal for me and it's the thing that will make me cave if it doesn't go away. I can only put up with it for so long. It feels like my stomach is inflamed and has swollen up so much that it's making my stomach feel as if it is too big for the area it has inside my body. Putting pressure on it slightly reduces the pain. When I put pressure on it I can feel the specific areas where it is sore. Almost like when you rub a sore muscle. I just can't stand that pain. It's that much harder when I know that one shot and it's gone instantly.
For some reason I've noticed that even if it hurts the pain disappears if I take a hot bath. Of course 30-40 minutes later the water starts to cool and then the pain starts coming back and will come back when I get out. If I'm lucky the bath will make it disappear and it won't come back. I've heard of pregnant mothers having "tub births" in their homes and supposedly the pain is significantly reduced. Of course it probably looks like the tide of Omaha Beach on D-Day, but there seems to be something to that.
Aside from that stomach/mucus situation, another symptom I really hate is feeling constantly cold. It gives me goosebumps for hours. It isn't a symptom that makes me cave, but it makes the cold weather outside almost unbearable. Getting outside and moving around is important for my recovery, but the cold makes me feel like just staying inside and only being cold, instead of freezing cold.
![:\](https://bluelight.org/xf/BL_Images/Orig_Emoji/wrygrin.gif "wry grin :\")