Your doing awesome! Don't stress, the weight gains each week can vary hugely! It might be 90 this week, but 250 next week!
We're feeding around every hour through the day here atm. Lots of reasons, one being weight gain. We're averaging 100gm a week.
Keep offering like Barb says, at every grizzle.
I'm usually feeding Summer every 20 - 30 minutes, if not continuously from around 5 - 6ish til 8 or 9 every night. Thats her cluster feeding time. She'll usually go down sfter this & sleep til 4 or 5 am, then we're 2 hourly til 8ish, then mostly hourly through the day