Oo normal yan, especially first time! Maraming sa amin na pregnant felt the same pains and aches sa balakang starting around 2 months, kaya don't worry too much But since this is your first pregnancy at gusto mo sure, best talaga na i-mention mo sa OB mo sa next check-up para ma-rule out kung may other concerns, and they can give you safe exercises or stretches na makakatulong. Congrats sa pregnancy, mamsh!