Furthur along than what you thought?

Has anyone else ever gotten pregnant thought you were only a few weeks then go to the doctor and find out your furthur along than expected?? I feel like I might be but not sure because they didn't say anything when I went in for my yearly and when I first tested it was a faint positive and I got my period like normal the month before. But I feel bigger than 6 weeks and my mom said with her pregnancies she didn't get symptoms til like 8-12 weeks when I got symptoms at like 4. Which I know it can be different than hers but could be the same. Any thoughts??