Advice please , think I might be pregnant

I think I might be pregnant ,I had my last period on the 13th of April and expected my next one on the 4th or 5th of May , but i had no sign , I then had very very light bleeding on the 11th and 12th of May but no cramps which I usually suffer really bad from , I've been extremely tired and very grumpy but I wasn't sure if it is still far to early to tell , does this sound as if I may be pregnant ? Any advice or help would be appreciated thanks in advance