Separation Anxiety Starts now

It's been about 2 weeks since i started attending playgroup. Out of the 2 weeks, i missed school for youth day and 2 other days which i was sick. I am still learning to adapt going to school. I still cry when mummy hands me over to my teacher at the door and when i am waiting in line to go home. In between lessons, i will suddenly think of mummy and shed some tears. I guess it really take time getting used to this new change in my life. Mummy read from reports that separation anxiety starts from 18-24 mths and i am currently in this phase. Just today, i kept crying for mummy when i am at grandma's place. When i hope i will get better and be more independent when i hit 24 mths.