When I was a college student living in Paris in a French student residence , I was hanging out with some friends who were discussing music and singing along with some CDS that were playing…and just to get into the conversation probably, I said to one of my best (French) friends, “Tu chantes bien quand même.” (You sing well, nevertheless/still).  And the reply was, “C’est quoi ce quand même?”  (What’s this quand même?).  And my response was “Je ne sais pas.”  (I don’t know).  I had just said something that made really no sense in the context of that conversation.  I had probably recently learned or rather actively heard that word and was trying to use it.  We all do this – some more than others depending on the shy factor, willingness to take risks, etc.- but, it’s a natural part of language learning and although it can cause a little embarrassment at times (my face turned bright red, they said), it’s not a big deal.  

So, my point is that you should and must make mistakes as that is how we learn.  The more mistakes you make, the more you’re probably speaking in French and the more feedback you’ll probably get, which means you’ll be able to make necessary corrections to your active vocabulary and gain fluency.

Allez-y!  Faites plein d’erreurs!