Contractions at 13 weeks

[chopinetto]

I am 13+1 day pregnant with twins, for the past few days I can feel my stomach tighten and then relax. My doctor insisted that this is just gas but it really feels like contraction.
Yesterday I was down with stomach bug and this intensified during that time. These two are ivf babies so I am worried sick all the time. Anyone had something similar?

It’s likely every thing stretching, it’s very normal at that point with one baby to feel everything starting to stretch so I imagine it’s a little more intense with 2.