ok firstly if ur 3-4 months pregnant ur hcg right now would be VERY low, i know this because i didnt find out i was preg with my first till 15 weeks gone and all preg tests (urine) were NEG not even a hint of a line, this was due to hcg not being needed anymore as placenta had well taken over, with this preg i tested at 10 weeks just for fun and below and behold the faintest line id ever seen i was very scared but i had a scan 2 days later and baby was fine doing well and still is
the only way i got a pos test in my first preg was because i had bloods done, its pointless now taking urine tests for the reason i said above, u should go for bloods and a scan to know for sure, it was only at my scan with my first baby that i found out i was 15+5 days along
also as for ur tummy being to big for 3 months preg thats not true mine is the same if not a tiny big bigger and im just 13 weeks
go have bloods hunny and keep us updated, id rather not state if i think ur preg or not due to faulse hope my only advice is get tested and get scanned fast as u ahvent taken any folic acid and if u are preg u must see baby and make sure everything is doing ok with him/her xxxx