Labour begining or normal?

hi.. so today i have been having some lower back pain and strange twinges.. my back is like a constant dull ache and every so ofter i get like a pulling/squeezing at bottom that last maybe 10 seconds and then goes away.. its quite painful but not breathtaking, also hav had some strange feelings in stomach but not really painful.. im 35+3 weeks with my second but first was induced so dont no wat its like naturally.. should i be worried or is this normal