What happens at 6 week miscarriage

I'm still ttc nearly 3 years now I had a loss last year in September at 7-8 weeks and the full sack passed. I was checked over woth ultrasounds and they said everything had defiantly passed. Then I had another loss the December at 6 weeks but I only bled for little as 3 days and nothing passed so I phoned the hospital they said it's okay probably a chemical. But since then I haven't been able to concieve I had hsg that shown dye didn't pass through either tube so I'm worried there may be something blocking. The Dr said it's probably muscle spasm but I'm sure it's something as I can't conciece since.

I'm now waiting for a laporoscopy but can takes months 😔

Should something of passed out at 6 weeks ?