Spotting/bleeding

I have been spotting more often mid-cycle as well as a few days before and after I have my period. Sometimes it is just for a few hours, but other times it is for a few days. Lately, it has also been happening 75% of the time I have sex. Before this year, I have rarely had any spotting and now it seems that I could start spotting or lightly bleeding on any given day. Is this normal? I have no idea what is going on. Is this something that happens as women age? Last year I turned 30 years old. Help, please!