mine were 18000 at 5 weeks
Doesn't seem too high to me. My levels were at 3500 when I was just about 4 weeks. At the time my doctor thought I was maybe 5-6 weeks along but she said the HCG levels have such a large range it is hard to tell. Well the reason I found out I was 4 weeks when I had the 3500 test is that I had a scan the following week due to some spotting.... Well the reason for the higher than expected level was it was twins!
I wouldn't worry to much. High levels are a good thing.. except for the morning sickness :-)
It seems high to me, but I know we're all different. My first beta was 248, then three days later it was 420. The next week (at 5 weeks) we had our first u/s. Best wishes :)