I am sorry to hear you are worried about your Dachshund. My name is Rebecca. I am a veterinarian and will do my best to help.
How old is she? Is this second heat coming 6 months after the first?
Dogs usually have a bloody discharge for 3 weeks when they go into heat, so it is not unusual for her to be having a red discharge after a week. That would actually be normal, and would continue for a couple weeks more.
Is she eating and drinking normally? Is she normally active, and moving about normally? The first thing we always worry about when a Dachshund screams in pain for no apparent reason is back or neck pain from an inflamed disc in the spine.
I just did some research, and found a number of references to dogs that seem to have back pain or joint pain when they go into heat, but the reason is unknown. I would have her checked out by your veterinarian and if she seems healthy and this seems to be a normal heat cycle, giving her pain or anti inflammatory medication may help.
Let me know what else I can answer or help with, and let me know how she is doing. Rebecca