YES. I had my first daughter when I was 18. People don't do it so much anymore now that she's 11 and obviously has turned out to be an awesome little lady (I must've done something right...!) For many people it is a moral issue - someone who "gets themselves knocked up" certainly can't be a responsible parent, right? (Ha!)
Many of the BEST parents I know are younger parents. I LOVE being a young mom. I think the key is doing what you FEEL is right and not worrying what others think.
When my first daughter was born I have a couple of distinct instances where people treated me poorly or like I didn't know what I was doing as a mother. So, consequently, I, at times, did go into new situations assuming that people were going to treat me that same way - whether they were or not - so I went in defensively. This didn't do me any good, so I'd advise assuming the opposite.
Assume everyone is going to respect you the way they should and then if they DON'T, then you can deal with it. But, if you assume the best - then many times that positive attitude will influence those you encounter.
Just know that Mama knows best - no matter what age you are.
Take care - and God Bless.
-J.