Do I include my January-February 2018 RRSP contributions made to employer RRSP? They're not listed on my T4. Do I add them separately in the RRSP section of TurboTax?

Yes, you are required to report contributions made in the first 60 days of 2018 on your 2017 tax return.  You should have received RRSP slips from the institution with whom the contribution was made to even though it was via your employer.  And yes, you will need to report it within the RRSP section of TurboTax.