Your numbers are still rising and that's always a good sign. Everyone's Hcg levels will differ, from pregnancy to pregnancy. Mine were very low with my first, and I had a healthy baby girl.
Spotting is normal as long as it's not bright red, and you don't have cramping.i would still call your doctor and let them know about the blood.
As far of twins, I'm sorry I've never had them so I wouldn't know what to expect for hcg levels
Hi I'm 5 weeks and 3 days. I just left the doc office and like you my levels are up there. She actually told me that next week we should be able to hear the heartbeat cuz hcg levels are high and rising. And like you i also thinking twins. They run in the family. Talk to your doc and good luck
It can take anywhere from 48-72 hrs for your levels to double and it sounds like your having implementation bleeding. Try not to worry too much!