Possibility of pregnancy?

Okay so let me start off at the beginning. My hubby and I already have a 20 month old. We aren't really trying to conceive just yet but I have a gut feeling I'm pregnant.

My last period was April 21st and they are very regular. When ever my hubby and I have sex,he never uses the condom until the very end.

From May 1st-7th was my fertility period. May 1st we had sex but at the end he used a condom,same for May 6th,8th and 11th. May 4th we didn't use protection and he didn't pull out. I am not on any birth control and haven't been for a long time now.

May 6th I ovulated and have experienced cramps from that day until the May 11th. 8 DPO-May 14th I noticed what I have read to be as implantation bleeding. I went to the bathroom,wiped and saw pink spots of blood after wiping a third time it disappeared and I have not had any bleeding since. May 15th-it seems I need to urinate more but I don't keep track of it so I'm not too sure. May 16th I started getting nauseated and its now the 18th and I still have it. I woke up this morning and got nauseous and also felt dizzy. I also have a craving for chicken strips and honey mustard dressing but I'm not sure if I am craving it or if it's just me being hungry.

I have fatigue and I am more tired than usually. My nipples are very sensitive and I have had excessive discharge.

According to the calender my period is due the 20th and I usually cramp 2 days before my period is due and I have had no cramps at all.

I plan on testing the 22nd but what do you all think. Could I be pregnant?