Aih, at 30 weeks memang baby boleh tendang sana sini, tapi yang you describe, sakit + cramp + kebas, tu boleh jadi banyak benda, tidak semestinya tendangan je (kadang-kadang gas, stretching, atau bahkan position of baby yang tekan organ lain). I'd really suggest you mention this to your doctor or midwife next checkup, especially since it's making you uncomfortable, they can check if baby's position okay and if anything else is going on, so you can rest easy. A few of us mummies rasa benda macam ni, and most of the time it's normal, but better safe than sorry kan, especially first baby. Hang in there!