I am 13 weeks and 5 days pregnant and last night at like 6am I woke up to go to the bath room and had slight bleed but nothing since then it's now 5pm not really any cramping only slight on my side which has happens on and off way before last night but I did have slight discomfort but when I pass gas it goes away should I have a doctor check up?

You could for the peace of mind. Some women will have some spotting or bleeding in pregnancy and usually it is not a concern as long as it does not continue or involve severe cramping. Common reasons can be a recent pelvic exam or intercourse. It's a good idea to have it checked if there is any doubt.

Certainly if it causes you concern you can always at least ring your doctor and see if he or she would like you to be seen.