Can you do gardening while pregnant?

Yesterday I planted some tulip bulbs. Today I continued doing this. Our soil is compacted clay & is VERY hard to dig. Anyway afterward I noticed I have a sore lower abdomen w/ some cramping (no bleeding or spotting). I'm 14 weeks & quite worried I may have put my baby in jeopardy. Anyone else done strenuous activity & had a successful pregnancy? Should I be concerned?