Dieting and strange cycle?

Georgina

So iv been doing slimming world 3 months, lost a stone and half so far. However my cycle has messed up,

1st month my period was almost 2 week late,

2nd month it came on time but only lasted 2 days

This month it hasn’t come at all, done 4 hpt all negative yet 13 days later I still have no period,

We’re trying for baby number 2.

How do I re regulate my periods? Does dieting and loosing weight effect your periods?

Please help if you can x