Lynn,
I highly recommend getting tubes put in for your son ASAP.
I have 4 children and have experienced a variety of issues regarding "fluid in ears".
1st child - no infections, no problems, speaking well at 18-24 months.
2nd child - constant fluid in ears, and doc kept telling me "it's just fluid", and not to worry - we did have a few ear infections... but, mostly "just fluid" - which they don't treat... well, at 20 months, we did get tubes.... This child ended up in speech therapy at age 3 due to speech issues caused by not being able to hear from birth to 20 months
3rd child - same thing as 2nd child, and I grew more and more annoyed w/ doc.. but, again, trusted him and waited and waited.. got tubes at 20 months, and this child also ended up in speech therapy.... starting at 22 months and is still in speech therapy... (he's now 3 1/2)
4th child - I wasn't taken any chances and after 3 ear infections/"flud in ear" I insisted on tubes at 6 months (he now didn't dare disagree with me) which we did... and low and behold, this child was talking up a storm at 17 months.. (she's now just 2) and literally, talks about as well as my 3 1/2 year old....
I completely attribute the speech issues to not being able to hear well. they are totally related.. think about it, how can they learn to talk properly if they can't hear what we are saying clearly.....
Oh - and I'm no longer with that peditrician that made me wait and wait for tubes... I wish I would have left him earlier and followed my gut... oh well, live and learn... and share experience with others, i suppose.
Again - I highly recommend getting tubes for your son now....
Good luck with your decision,
K.