Pregnancy

Is it going to be more difficult to get pregnant in the early 30's compare to early 20's? Last couple of months me and my husband were just talking about starting a family soon. Twice we BD-ed on near ovulation day and on ovulation day. Which falls on February and last month(July). My next period is in 4 days. I noticed that the two times we BD-ed near ovu and on O.D(which is in July) my allergic rhinitis flares up like crazy. Took some antihistamine it won't help.