Growth Spurt? Or ready for baby food?

So, my daughter usually sleeps from like 9 or 10 at night until like 5 to 7am.. She's been doin that for like a month now. She is 3 and a half months old. Well last night and the night before she wants to wake up every 2-3 hours to eat. she will eat 5-6 ounces. She gets cereal in her bottle before bed, so at like 8:30pm or so... Could this be a growth spurt why she's eating so much, or could she be ready for babyfood (stage 1's of course). I have let her taste babyfood a few times, and she was ok with it.