Not weird, just a little delayed. The two year molars come in, *on average*, around 2 years old, but for some kids that means 15 mos and for others it could be 36 months. Just two fewer teeth to clean for now!
My dd had her lower 2 come in about 4 months ago. She turned 3 last week and no sign of the top 2 yet. She was at the dentist for a cleaning last week as well and he was no concerned, just said they will come in at some point.